Fuel Supply System - All Engines Audi A6 C5

General repair notes

1. Observe all safety precautions. See «SAFETY PRECAUTIONS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__safety-precautions) .
2. Observe the rules of cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .

Checking fuel pump relay and activation

See appropriate MULTIPORT FUEL INJECTION (MFI) article.

Safety precautions

The following measures must be made before beginning work on the fuel system

1. Disconnect ground strap from battery with ignition off.
2. Open fuel filler cap briefly and close again.

When removing and installing of components from filled or partly filled fuel tanks pay attention to the following

Rules of cleanliness

1. Thoroughly clean fuel system line and hose connections and the surrounding area before disconnecting.
2. Place removed components on a clean surface and cover. Use plastic sheeting or paper. Do not use fluffy rags that could leave lint!
3. Carefully cover over or seal any components that have been opened if repairs are not carried out immediately.
4. Install only clean parts: Do not remove replacement parts from the packaging until immediately before they are to be installed. Do not use parts that have been stored without packaging (e.g. in toolboxes, etc.).
5. When the fuel system is opened: Avoid working with compressed air whenever possible. Avoid moving the vehicle if possible.

Fuel supply, Front Wheel Drive (FWD)

Note. Secure all hose connections with the correct hose clips (same as original equipment). Hose VAG1921 clip pliers are recommended when installing spring-type clips. Always replace sealing rings and gaskets when assembling.

Fuel tank with sub components, component overview

Part I

Note. The following list refers to items in (Scheme 1).

1. Fuel return line From engine Mark before disconnecting Observe arrow direction on flange Clip in right front at fuel tank
2. Fuel supply line From fuel filter Mark before disconnecting Observe arrow direction on flange Clip in right front at fuel tank
3. Bolt M8 x 35 with attached washer 23 Nm (17 ft lb) Secures fuel filler neck and Ground wire -item -9-.
4. Over flow hose
5. Rubber cup
6. Retaining ring
7. Fuel filler cap
8. Seal Replace if damaged
9. Ground connection Installation position. For checking procedure, see «CHECKING PROCEDURE OF GROUND (GND) CONNECTION»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__checking-procedure-of-ground-gnd-connection) . Make sure that both terminals have good electrical contact Mount terminal with bolt - 3 - for fuel filler neck. After installing, measure resistance using multimeter (Fluke 83 or, equivalent) between metal ring of fuel filler neck and bare metal part of body. Specified value: approx. 0 ohm
10. Vent line To EVAP canister
11. Vent line
12. Vent line
13. Fuel tank Removing and installing, see «FUEL TANK WITH ATTACHMENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines)
14. Holding clamp Observe different lengths Installation position: stop (hole) points toward front of vehicle
15. Bolt M8 x 28 with attached washer 23 Nm (17 ft lb)

Scheme 1

Note. The following list refers to items in (Scheme 2).

Part II

1. Fuel filler neck With expansion tank
2. O-Ring Always replace
3. Gravity valve Not available as replacement part To remove, unsnap valve and pull to top from filler neck Checking operation: Valve upright: open Valve turned 45De from vertical: closed
4. Tank protection valve Mounted (clipped on) to fuel filler neck Ventilates tank to equalize pressure
5. Ground (GND) connection Installation position: For checking procedure, see «CHECKING PROCEDURE OF GROUND (GND) CONNECTION»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__checking-procedure-of-ground-gnd-connection) . Ensure tight fit connection of connector at filler neck Tighten contact terminal (tongue) with bolt to fuel filler neck -item 3-. After installing, measure resistance using multimeter (Fluke 83 or equivalent) between metal ring of fuel filler neck and bare metal part of body. Specified value: approx. 0 ohm
6. Sealing ring Installation position: sealing lip faces fuel filler neck
7. O-Rings Different size Always replace
8. Vent valve Removing and installing, checking, see «VENT VALVE REMOVING, INSTALLING AND CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
9. Hose coupling To remove, press down on release tab
10. To EVAP canister

Scheme 2

Checking procedure of Ground (GND) connection

Note. Check installation position with fuel tank removed

1. Install Ground (GND) connection -arrow- as shown.
2. Make sure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
3. Check if contact terminal (tongue) at fastening hole is properly locked in.
4. Hold terminal tongue -1- with bolt -2- to fuel filler neck.

Scheme 3

Scheme 4

Removing

1. Fuel tank removing, see «FUEL TANK WITH ATTACHMENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. To remove unclip valve (laterally) from expansion tank.

Scheme 5

1. Close flange -3- with hand. (Scheme 5)
2. Blow into flange -1-: Knob -2- in rest position: It should not be possible to blow through Knob -2- pressed in direction of arrow: It must be possible to blow through.

Fuel tank, draining

1. Procedure on fuel tank more than 3/4 full, see «A - PROCEDURE ON FUEL TANK THAT CONTAINS MORE THAN 3/4FUEL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Procedure on fuel tank less than 3/4 full, see «B - PROCEDURE ON FUEL TANK THAT CONTAINS LESS THAN 3/4FUEL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__b-procedure-on-fuel-tank) .

Special tools and required equipment

1. VAS 5190

Work sequence

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .
3. Vehicles with coded radio/navigation system (RNS) coding, refer to vehicle owner's manual if necessary.

Scheme 6

1. Remove cover above battery -arrow-.

Note. On vehicles without battery cover: Remove plenum cover.

Scheme 7

See Caution before beginning repairs on the electrical system. See FUEL SUPPLY, FRONT WHEEL DRIVE (FWD) .

Scheme 8

1. Disconnect battery Ground (GND) cable -arrow- with ignition switched off.

Scheme 9

1. Remove cone piece -2- from hose -1- of VAS 5190.
2. Mark location on hose -arrow- with a piece of insulating tape.
3. Push test hose -2- -arrow- into fuel filler neck until marking is lined up with fuel filler neck.
4. a = 1115 mm
5. Remove fuel cap from filler neck.
6. Install hose -1- of VAS 5190 to filler neck of the fuel tank.
7. Push suction hose into fuel tank up to marking tape -arrow

Scheme 10

Note. Mark the position of the hose with a piece of tape -arrow-. a = 1050 mm At the lower end of the filler hose in the fuel tank-1- is a check plate - located, which is to be opened via the hose (suction hose) -2-. For this reason push hose to marking. Do not push hose any further than the marking into the fuel tank. Otherwise the hose moves upward and only a little amount of fuel in sucked out. If hose is hard to push into fuel tank, coat hose lightly with clean engine oil. Do not use under any circumstances silicone based lubricants.

Scheme 11

1. Drain fuel tank via fuel filler neck as much as possible.
2. Carefully remove suction hose.
3. Remove ring nut for fuel delivery module. See «FUEL PUMP MODULE, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
4. Suction rest of fuel via opening for fuel delivery module.

B - Procedure on fuel tank that contains less than 3/4fuel

1. Remove ring nut for fuel delivery module. See «FUEL PUMP MODULE, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Suction fuel via opening for fuel delivery module.

1. VAG1383 A with VAG1359/2

Scheme 12

Scheme 13

1. Observe safety precautions under «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .
3. Obtain radio code on vehicles with coded radio/integrated radio.
4. Remove cover above battery -arrow-. NOTE: On vehicles without battery cover: Remove plenum cover.
5. With ignition switched off, disconnect battery Ground (GND) strap -arrow
6. Open fuel filler cap briefly and close again.

Limousine

1. Remove cover for sender for fuel gauge located under liner in luggage compartment.
2. If necessary; fold the right rear seat back forward.

Scheme 14

Avant

1. Remove cover for sender for fuel gauge located under liner in luggage compartment. See «CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) or «CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) .

All

Scheme 15

Scheme 16

Scheme 17

Scheme 18

1. Remove cover -arrow- for fuel tank sender.
2. Carefully release 4-pin harness connector for sender for fuel gauge in direction of -arrow- and disconnect.
3. Thoroughly clean area around fuel filler neck.
4. With the fuel filler flap open, loop -1- where available.
5. Pry locking collar -arrow- in the rubber cup (around the filler neck) out.
6. Push rubber cup inward.
7. Open fuel filler cap briefly and close again. NOTE: Do not remove caps.
8. Remove right rear wheel housing unit. See «WHEELHOUSING LINERS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment) .
9. Remove bolt -1- for fuel filler neck.
10. Disconnect line -2- to EVAP canister and unclip line from retainer -arrow-.
11. Remove cover in front of rear axle -arrows-.

Scheme 19

Vehicles with level control system

1. Remove level control system sensor -G84- at body -arrows

Scheme 20

All

Scheme 21

Scheme 22

1. Disconnect fuel supply and return lines -arrows-.
2. Position VAG1383A Engine/Transmission jack for support under fuel tank. WARNING: The fuel tank must be empty when removing in order to reduce weight. If necessary empty fuel tank.
3. If necessary, mark retaining straps for easier re-installation.
4. Remove fasteners -1- through -6- and remove fuel tank support straps, if necessary mark straps for later installation.
5. Lower fuel tank using VAG 1383A engine/transmission jack while turning it to left.

Note. Arrow- points toward the front of the vehicle.

Installing

Installation is the reverse of removal, however note the following

Note. Replace all hose clamps with the same type of clamp that was used in production. See Parts catalog. Use VAG 1921 pliers or similar tool to install spring clamps. Always replace seals and O-rings.

Scheme 23

Scheme 24

Scheme 25

1. Make sure that return and supply lines at right-front side of fuel tank are secured in retainer -arrows-.
2. Route and connect Ground wire -arrow- as shown.
3. Make sure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
4. Check if contact terminal (tongue) at fastening hole is properly locked in.
5. Hold terminal tongue -1- with bolt -2- to fuel filler neck.

Scheme 26

1. After tightening fuel tank support straps, press cap-1-onto screw-2-in spare wheel well. See Caution for connecting Telematics battery under «FUEL SUPPLY, FRONT WHEEL DRIVE (FWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-front-wheel-drive-fwd)
2. With ignition switched off, reconnect battery Ground (GND) strap. NOTE: Carefully install the cover for the plenum chamber under the windshield to prevent water from entering the pollen filter or the heater.
3. After reconnecting battery, insert radio code. NOTE: Using switches, fully close power windows up to stop. Then, operate all power windows for at least 1 second in "close" position to activate "one touch" opening/closing function. Set time on clock. Generate readiness code: See appropriate ON-BOARD DIAGNOSTIC (OBD) article.

Tightening torques

TIGHTENING TORQUES: FUEL TANK (FWD)

Fuel pump module including sender for fuel gauge, component overview

Note. The following list refers to items in (Scheme 27).

1. Sender for fuel gauge - G For checking, see «SENDER FOR FUEL GAUGE-G-, CHECKING - FRONT WHEEL DRIVE (FWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . For removing and installing, see «SENDER FOR FUEL GAUGE-G, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Fuel strainer Cannot replace individually Clean if dirty
3. Fuel pump delivery module Can only be replaced as a unit together with closing flange Removing and installing, see «FUEL PUMP MODULE, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Fuel pump electrically checking, see «FUEL PUMP, CHECKING ELECTRICALLY»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Delivery rate checking, see «FUEL PUMP DELIVERY RATE, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Pressure checking: See appropriate MULTIPORT FUEL INJECTION (MFI) article.
4. Closing flange Not available as replacement part Installation position: Observe marking of arrow
5. Fuel return line From engine Mark line before disconnecting Observe marking of arrow on closing flange
6. Fuel supply line To fuel filter Mark line before disconnecting Observe marking of arrow on closing flange
7. Seal Always replace When installing fit seal fry into opening of fuel tank
8. Union nut 80 Nm (59 ft lb) Use 3217 ring nut spanner to remove and install
9. Harness connector For fuel pump module and sender for fuel gauge To disengage, see «HARNESS CONNECTOR UNLOCKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
10. O Rings Always replace Check installation position
11. Return line Disconnect when removing fuel delivery module
12. Accumulator housing With suction pump Displayed in Fig. without fuel tank

1. In order to disconnect the multi-pin harness connector at the fuel delivery module, unlock connector. Using screw driver-arrow

Scheme 27

Scheme 28

Special tools, test equipment and auxiliary items

1. 3217 Ring Nut Spanner
2. VAG1348/3A with VAG1348/3-2
3. VAG 1526 A
4. VAG 1594 A

Scheme 29

Scheme 30

1. Battery fully charged (at least 12 volts)
2. Fuse S228 OK (socket 28)
3. Relay in position -4- in relay panel (central electric) behind storage shelf OK
4. Fuel filter in good condition
5. Ignition switched off

Scheme 31

1. Open cover for fuse panel on driver's side under instrument panel.
2. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
3. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 arrow-.
4. Connect test probe to Battery Positive Voltage (B +).
5. Press remote switch. Fuel pump must run (pump will be audible)

Note. The pump is very quiet, make sure area is quiet while testing.

If the fuel pump does not run

1. Remove cover for closing flange under luggage compartment liner.

Limousine

1. Remove cover for sender for fuel gauge located under line in luggage compartment.
2. If necessary; fold the right rear seat back forward.

Avant

1. Remove cover for sender for fuel gauge located under liner luggage compartment. See «CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) or «CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) .

All

Scheme 32

Scheme 33

Scheme 34

1. Remove cover-arrow- for fuel tank sender.
2. Carefully release 4-pin harness connector and disconnect.
3. Set multimeter (Fluke 83 or equivalent) to 20 volt DC range. Using adapter wire from VW1594 connector test kit connect to terminals-1- and -4- of harness connector.
4. Press (and hold) remote switch and read voltage. Specified value: approx. Battery Positive Voltage (B)

If specified value is not attained

1. Eliminate short circuit in wiring using wiring diagram.

Specified value is attained but the fuel pump does not run

Scheme 35

Scheme 36

Scheme 37

1. Mark fuel supply line-2- and return line-1- and disconnect from closing flange.
2. Remove union nut using 3217 ring nut spanner.
3. Remove closing flange with seal from tank opening.
4. Check that electrical wires between flange and fuel pump are connected and test for continuity.

If no wiring malfunction is detected

1. Fuel pump is faulty. Replace fuel delivery module. See «FUEL PUMP MODULE, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Install closing flange. See «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Special tools, testers and auxiliary items

1. VAG 1348/3A with VAG 1348/3-2
2. Measuring container

Requirements for test

1. Battery voltage not less than 12 V
2. Fuel filter OK
3. Ignition switched off

Scheme 38

Test sequence

1. Open fuse box cover on left side of the instrument panel.
2. Pull fuse No. S228 off fuse holder (left row, 5th large fuse from top).

Scheme 39

Scheme 40

1. Connect remote control V.A.G 1348/3A with adapter lead V.A.G 1348/3-2 to right-hand fuse socket of fuse No. 28-arrow.
2. Connect clamp to vehicle battery (+ ).
3. Remove filler cap from fuel tank filler neck.
4. Remove engine cover -arrow-.

Scheme 41

Scheme 42

1. Disconnect fuel return hose from fuel rail.
2. Connect extension (test) hose -arrow- to fuel rail and hold end of hose in measuring container.
3. Operate remote control for 15 seconds (keep button pressed).
4. Compare the quantity of fuel delivered with specification. *) Minimum delivery cm 3 /15 seconds **) Voltage at fuel pump with engine stationary and pump running (approx. 2 volts less than battery voltage).
5. Connect fuel return line with new hose clamp.

Scheme 43

Scheme 44

1. 3217 Ring Nut Spanner
2. 3307 Fuel Pump Wrench

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .

1. Remove cover above battery-arrow-.

Note. On vehicles without separate battery cover: Remove plenum cover.

Scheme 45

1. Disconnect battery Ground (GND) strap -arrow- with ignition switched off.

Limousine

1. Remove cover for sender for fuel gauge located under liner in luggage compartment.
2. If necessary; fold the right rear seat back forward.

Avant

1. Remove cover for sender for fuel gauge located under liner in luggage compartment. See «CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) or «CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) .

All

1. Remove cover arrow- for fuel tank sender.

Scheme 46

Scheme 47

1. Carefully release 4-pin harness connector-arrow and disconnect.

1. Mark fuel pressure line-2- and return line-1- and remove from closing flange.

Scheme 48

Scheme 49

Scheme 50

Scheme 51

Scheme 52

1. Remove union nut using 3217 ring nut spanner.
2. Lift closing flange and seal from tank opening.
3. At inside of closing flange disconnect harness connector-1 for sender for fuel gauge. NOTE: Harness connector-2 remains connected at fuel pump.
4. Remove return line-3- at inside of closing flange while depressing release tab of hose connector.
5. Insert 3307 fuel pump wrench through tank opening onto fuel pump module.
6. Using 3307 fuel pump wrench, turn fuel pump module to left approx. 15 to stop and lift unit out. Notch-1- lines up with mark-2- (bayonet lock)
7. Remove fuel pump with pump module housing.

Installation is the reverse of removal, however note the following

Note. Replacement hose clamps must be the same type of clamp that was used in production. See Parts catalog.

Scheme 53

Scheme 54

Scheme 55

Scheme 56

Scheme 57

Scheme 58

Scheme 59

1. Install fuel pump module into tank with notch-1- on fuel pump module lining up with marking-2- on outside of accumulator. It should feel that it is possible to press fuel pump module down. NOTE: To better show the procedure, the accumulator housing is shown without the fuel tank.
2. Insert 3307 fuel pump wrench through tank opening onto fuel pump module.
3. Using 3307 fuel pump wrench, turn fuel pump module approx. 15 to right to stop. Notch -1- must then align with marking-3-.
4. Install return line-2- on underside of closing flange. NOTE: Before installing the closing flange, moisten the O-rings and the seal for the closing flange with fuel. Always replace O-rings for return line.
5. Connect harness connector-1- for fuel gauge sender to closing flange. (Scheme 57)
6. Place new closing flange seal dry into opening of fuel tank
7. Insert closing flange into tank opening and note position
8. Mark on closing flange-arrow-1-must line up with mark on fuel tank-arrow-2-. NOTE: The black-arrow- points toward the front of the vehicle. Do not pay attention to "TDI" marking on fuel tank
9. Tighten union nut to 80 Nm (59 ft lb).
10. Reconnect 4-pin harness connector
11. According to previous markings, install fuel supply line-2-and return line-1-.

See Caution for connecting Telematics battery under FUEL SUPPLY, FRONT WHEEL DRIVE (FWD) .

1. With Battery re-connected, remember to activate electrical equipment (radio, clock, window switches) according to operating instructions.
2. For further measures after battery voltage is re-connected refer to: See appropriate MULTIPORT FUEL INJECTION (MFI) article.
3. Generate readiness code: See appropriate ON-BOARD DIAGNOSTIC (OBD) article.

Tightening torque

TIGHTENING TORQUES: FUEL PUMP MODULE (FWD)

Scheme 60

Scheme 61

1. VAG1526 A
2. VAG1594 A

Checking procedure

Limousine

1. Remove cover for closing flange under luggage compartment liner.
2. If necessary; fold right rear seat back forward

Avant

Scheme 62

Scheme 63

1. Remove cover for sender for fuel gauge located under liner in luggage compartment. See «CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) or «CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) .
2. Remove cover for closing flange under luggage compartment liner.
3. Release 4-pin harness connector-arrow- and disconnect.
4. Using multimeter (Fluke 83 or equivalent), measure resistance between both terminals-2- and-3- of closing flange. Tank full: specified value approx. 270 ohm Tank empty: specified value approx. 70 ohm

If reading is zero ohms or infinity ohms (open circuit), there is an open or short circuit inside the fuel tank.

Scheme 64

Note. In order to test the maximum and minimum values for "tank full" and "tank empty", remove fuel pump delivery module. See FUEL PUMP MODULE, REMOVING AND INSTALLING , and pivot or slide the floats of the two sensors all the way to their top and bottom positions.

When the fuel gauge sensor is removed, the float will travel further and the specifications are

FUEL GAUGE SENSOR RESISTANCE SPECIFICATIONS (FWD)

Scheme 65

1. Observe safety precautions. See «SAFETY PRECAUTIONS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__safety-precautions) .
2. Observe rules of cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .
3. Remove closing flange for fuel delivery module. See «FUEL PUMP MODULE, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
4. Carefully remove closing flange together with fuel pump module and set aside.
5. Remove harness connector for sender for fuel gauge on inside of closing connector.
6. Remove sender from accumulator housing while pressing down on release tabs (lower)-arrow-.

Note. To make the illustration clearer, the accumulator housing is shown without the fuel tank.

Installation is the reverse of removal, however note the following

1. Install sender for fuel gauge into guide at outside of accumulator and push in to stop.

See Caution for connecting Telematics battery under FUEL SUPPLY, FRONT WHEEL DRIVE (FWD)

1. Install closing flange together with fuel pump module ( «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) ) and observe notes concerning reconnecting battery.

Fuel supply, All Wheel Drive (AWD)

1. Obtain the anti-theft radio security code.
2. Switch the ignition off.
3. Disconnect the battery Ground (GND) strap.
4. On vehicles equipped with Audi Telematics by OnStar(R), switch-off the emergency (back-up) battery for the Telematic/Telephone Control Module prior to disconnecting vehicle battery. See «EMERGENCY BATTERY, SWITCHING OFF/ON»(/audi/a6/c5-1997-2001/remont/communication-devices/#radio-telephone-navigation-trip-computer__emergency-battery-switching-offon) .
5. After reconnecting vehicle battery, re-code and check operation of anti-theft radio. Also check operation of clock and power windows according to Repair Manual and/or Owner's Manual.
6. After reconnecting vehicle battery on vehicles equipped with Audi Telematics by OnStar(R), switch-on the emergency (back-up) battery for the Telematic/Telephone Control Module See «EMERGENCY BATTERY, SWITCHING OFF/ON»(/audi/a6/c5-1997-2001/remont/communication-devices/#radio-telephone-navigation-trip-computer__emergency-battery-switching-offon) .

Note. Secure all hose connections with the correct hose clips (same as original equipment) Hose VAG1921 clip pliers are recommended when installing spring-type clips. Always replace sealing rings and gaskets when assembling.

Fuel tank with attachments, component overview - vehicles with 6-cylinder engine and A6 Allroad

Note. The fuel filler neck with expansion tank can be exchanged separately. See FUEL FILLER NECK WITH EXPANSION TANK, REMOVING AND INSTALLING - VEHICLES WITH 6-CYLINDER ENGINE AND A6 ALLROAD .

Note. The following list refers to items in (Scheme 67).

1. Bolt M8 x 28 with attached washer 23 Nm (17 ft lb)
2. Speed nut For heat shield Must be securely fastened
3. Heat shield For fuel tank
4. Carrier panel
5. Strap Note installation position
6. Return line From engine Mark line before removal Observe direction of arrow Attach at right-front of fuel tank
7. Vent line Front part To Evaporative Emissions (EVAP) canister purge regulator valve -N80- Attached to upper part of fuel tank Remains attached when removing tank
8. Fuel supply line From fuel filter To fuel rail Mark line before removal Flow of fuel to and from tank -arrow- Located in right front
9. 2 Nm (18 in. lb)
10. Heat shield For fuel filler neck
11. Vent line Rear part To Evaporative Emissions (EVAP) canister Attached to upper part of fuel tank Remains attached when removing fuel tank
12. Bolt M8 x 28 with attached washer 25 Nm (18 ft lb) Used to fasten fuel filler neck and Ground (GND) wire -item 18-.
13. Overflow return hose
14. Fuel filler cap
15. Seal Replace if necessary
16. Retaining ring
17. Rubber cup
18. Ground connection Installation position/checking procedure, «INSTALLATION POSITION OF GROUND WIRE»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__installation-position-of-ground-wire) . Mount terminal with bolt (item -12-) for fuel filler neck. After installing, measure resistance using multimeter (Fluke 83 or equivalent) between metal ring of fuel filler neck and bare metal part of body. Specified value: approx. 0 ohms.
19. Fuel filler neck with expansion chamber Can be replaced separately. See «FUEL FILLER NECK WITH EXPANSION TANK, REMOVING AND INSTALLING - VEHICLES WITH 6-CYLINDER ENGINE AND A6 ALLROAD»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
20. Vent line To EVAP canister.
21. Fuel tank Removing and installing, see «FUEL TANK WITH ATTACHMENTS, REMOVING AND INSTALLING - VEHICLES WITH 6-CYLINDER ENGINE AND A6 ALLROAD»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines)

Scheme 66

Installation position of Ground wire

Note. Check installation position with fuel tank or fuel filler neck removed.

Scheme 67

Scheme 68

1. Route and connect Ground wire as shown (arrow).
2. Ensure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
3. Check if contact terminal (tongue) at fastening hole is properly locked in.
4. Hold terminal tongue -1- with bolt -2- to fuel filler neck.

1. Procedure on fuel tank more than 1/4 full, see «A - PROCEDURE ON FUEL TANK MORE THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Procedure on fuel tank less than 1/4 full, see «B - PROCEDURE ON FUEL TANK LESS THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__b-procedure-on-fuel-tank) .

1. 2012 A Key
2. VAS 5190

Scheme 69

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .

Scheme 70

1. Vehicles with coded radio/navigation system (RNS) coding, refer to vehicle owner's manual, if necessary.
2. Remove cover above battery -arrow-.

Note. On vehicles without separate battery cover: Remove plenum cover.

See Caution before beginning repairs on the electrical system under FUEL SUPPLY, ALL WHEEL DRIVE (AWD) .

Scheme 71

1. With ignition switched off, disconnect battery Ground (GND) cable. CAUTION: Fasten the grounding strap of the VAS 5190 to an acceptable ground location on the vehicle.

Scheme 72

Scheme 73

1. Remove cone piece -2- from hose -1- of the VAS 5190.
2. Mark location on hose -arrow- with a piece of insulating tape. a = 1205 mm
3. Remove fuel cap from filler neck..
4. Install hose -1- of VAS 5190 to filler neck of the fuel tank.
5. Push suction hose into fuel tank up to marking tape -arrow-. NOTE: Only push the suction hose up to the marking tape so that the fuel sender is not damaged.
6. Empty fuel tank.
7. Carefully remove suction hose
8. Remove the fuel sender and sealing ring. See «B - PROCEDURE ON FUEL TANK LESS THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__b-procedure-on-fuel-tank) .
9. Suction the remaining fuel out of both right and left fuel tanks. NOTE: The Suction device can be used in the same manner without the hose. Mark location on hose -arrow- with a piece of insulating tape. a = 1205 mm The suction hose -1- is installed completely when marking tape is at the edge of the fuel filler neck. If installation of suction hose is difficult, lightly coat hose with engine oil. Under no circumstances should silicone lubricants be used!

B - Procedure on fuel tank less than 1/4 full

Limousine

1. Remove cover for sender for fuel gauge located under liner in luggage compartment.

Scheme 74

Avant

1. Remove liner for floor covering.

See CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING or CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING .

All

Scheme 75

Scheme 76

Scheme 77

Scheme 78

1. If necessary; fold the left rear seat back forward.
2. Remove cover -arrow- for fuel tank sender.
3. Carefully release 2-pin connector -arrow- and disconnect
4. Remove union nut with wrench 2012 A.
5. Pull fuel supply sensor 3 together with seal out of fuel tank opening.
6. Draw off remaining fuel in left and right chambers of fuel tank through opening for sensor unit.
7. Re-install fuel supply sensor 3 with seal. See «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
8. Draw off remaining fuel in left and right chambers of fuel tank through opening for sensor unit using VAS 5190.
9. Re-install fuel supply sensor 3 with seal. See «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

1. Engine/transmission jack VAG 1383 A with universal support VAG1359/2

Scheme 79

Scheme 80

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .
3. Obtain radio code on vehicles with coded radio.
4. Remove cover above battery -arrow-.

Note. On vehicles without separate battery cover: Remove plenum cover.

See Caution before beginning repairs on the electrical system under FUEL SUPPLY, ALL WHEEL DRIVE (AWD)

Scheme 81

Scheme 82

Scheme 83

Scheme 84

Scheme 85

Scheme 86

Scheme 87

Scheme 88

Scheme 89

1. With ignition switched off disconnect battery Ground strap. WARNING: The fuel tank must be empty when removing in order to reduce weight. If necessary empty fuel tank. See «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines).
2. Remove rear seat bench. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames).
3. Remove cover for flange on fuel tank under rear seat bench (right side).
4. Carefully release 4-pin connector -arrow- and disconnect.
5. Remove center and rear silencers See appropriate EXHAUST SYSTEM article.
6. Remove heat shield for fuel filler neck above rear silencer (right side).
7. Remove rear axle: See appropriate REAR SUSPENSION article.
8. Thoroughly clean area around fuel filler neck.
9. With the fuel filler flap open, loop -1- where available.
10. Pry locking collar -arrow- in the rubber cup (around the filler neck) out
11. Push rubber cup inward.
12. Open fuel filler cap briefly and close again
13. Remove right rear wheel housing unit. See «WHEELHOUSING LINER, REAR»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment__wheelhousing-liner-rear).
14. Remove 2 bolts -arrows- for fuel filler neck underneath wheelhousing liner.
15. Disconnect line -1- to EVAP canister. (Scheme 87) WARNING: Fire Hazard. Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
16. Mark supply line -3-, return line -2- and vent line -1- and disconnect.
17. Disconnect vent line for EVAP canister -arrow- at rear of fuel tank. NOTE: The vent line remains attached when the fuel tank is removed.
18. Remove heat shields at left and right of fuel tank.
19. Support fuel tank using VAG1383A engine/transmission jack. WARNING: For weight reason the fuel tank must be empty when removing.
20. Remove fasteners -1- through -8- for support straps and carrier panel.
21. Lower fuel tank together with carrier panel -9-. NOTE: The -arrow- points toward the front of the vehicle.

Installation is the reverse of removal, however note the following

Note. Fasten all hose clamps with the same type of clamp that was used in production. Use VAG1921 pliers or similar tool to install spring clamps. Always replace seals and O-rings.

Scheme 90

Scheme 91

1. Route and connect Ground wire as shown -arrow-.
2. Ensure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
3. Check if contact terminal (tongue) at fastening hole is properly locked in.
4. Mount the terminal -1- with the bolt -2- for fuel filler neck. WARNING: After installing, measure the resistance using a multimeter (Fluke 83 or equivalent) between the metal ring of the fuel filler neck and a bare metal part of the body. Specified value: approx. 0 ohm
5. Ensure that fuel supply and return lines at right-front of fuel tank are properly installed in retainers.
6. Carefully install cover for closing flange with indentation positioned on top of connector.
7. Install right rear wheelhousing liner: See «WHEELHOUSING LINER, REAR»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment__wheelhousing-liner-rear) .
8. Install center and rear muffler stress free. See appropriate EXHAUST SYSTEM article.
9. Install rear axle: See appropriate REAR SUSPENSION article.
10. For further measures after battery voltage is re-connected refer to: See appropriate MULTIPORT FUEL INJECTION (MFI) article.
11. Generate readiness code: See appropriate ON-BOARD DIAGNOSTIC (OBD) article in ENGINE PERFORMANCE.

TIGHTENING TORQUES: FUEL TANK, VEHICLES WITH 6-CYLINDER ENGINE AND A6 ALLROAD

Fuel filler neck with expansion tank, component overview - vehicles with 6-cylinder engine and A6 Allroad

Note. The following list refers to items in (Scheme 93).

Scheme 92

1. 2 Nm (18 in. lb)
2. Heat shield for fuel filler neck
3. Hose connections For vent line to EVAP canister
4. Hose connections For vent lines to fuel tank When removing mark hoses for later installation
5. Hose connection For fuel filling duct
6. Hose connection For vent line for fuel tank ventilation
7. Ground (GND) connection To deter static electricity Installation position, checking procedure, see «INSTALLATION POSITION OF GROUND WIRE»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Ensure tight fit of connector and fasten connector with bolt for fuel filler neck -item 15-. After installing, measure resistance using multimeter (Fluke 83 or equivalent) between metal ring of fuel filler neck and bare metal part of body. Specified value: approx. 0 ohm
8. Rubber cup
9. Retaining ring
10. Seal insert For gas station fuel nozzle Replace if necessary Removing and installing, see «SEAL INSERT FOR GAS STATION FUEL NOZZLE, REMOVING AND INSTALLING - ALL ENGINES»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines)
11. Seal Replace if necessary
12. Fuel filler cap
13. Overflow return line
14. Fuel filler neck with expansion tank With valves and hoses Can only be replaced as one unit Removing and installing, see «FUEL FILLER NECK WITH EXPANSION TANK, REMOVING AND INSTALLING - VEHICLES WITH 6-CYLINDER ENGINE AND A6 ALLROAD»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines)
15. Bolts M8 x 30 with attached washer 23 Nm (17 ft lb)

Note. Check installation position with fuel tank or fuel filler neck removed

Scheme 93

Scheme 94

1. Route and connect Ground wire as shown -arrow-.
2. Make sure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
3. Check if contact terminal (tongue) at fastening hole is properly locked in.
4. Hold terminal tongue -1- with bolt -2- to fuel filler neck.

Scheme 95

Scheme 96

Scheme 97

Scheme 98

Scheme 99

Scheme 100

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines).
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness). For removing the filler neck with expansion tank, the fuel tank should not be over 1/2 full. If necessary, empty fuel tank refer to «A - PROCEDURE ON FUEL TANK MORE THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines). CAUTION: After reconnecting vehicle battery on vehicles equipped with Audi Telematics by OnStar(R), switch-on the emergency (back-up) battery for the Telematic/Telephone Control Module. See «EMERGENCY BATTERY, SWITCHING OFF/ON»(/audi/a6/c5-1997-2001/remont/communication-devices/#radio-telephone-navigation-trip-computer__emergency-battery-switching-offon). Vehicles with coded radio/navigation system (RNS) coding, refer to vehicle owner's manual if necessary. Remove cover above battery -arrow-. NOTE: On vehicles without battery cover: Remove plenum cover. See Caution before beginning repairs on the electrical system. See «FUEL SUPPLY, ALL WHEEL DRIVE (AWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-all-wheel-drive-awd). With ignition switched off disconnect battery Ground strap -arrow-. Thoroughly clean area around fuel filler neck. With the fuel filler flap open, loop -1- where available. Pry locking collar -arrow- in the rubber cup (around the filler neck) out Push rubber cup inward. Open fuel filler cap briefly and close again Remove heat shield for fuel filler neck above rear muffler -arrows-. NOTE: For easy access lift rear muffler out of hanger. Remove right rear wheel. Remove right-rear wheelhousing liner. See «WHEELHOUSING LINER, REAR»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment__wheelhousing-liner-rear). NOTE: To ease repair process, remove muffler from muffler hangers. Remove cover for EVAP canister below spare wheel molding. Remove vent line -arrow- from EVAP canister. WARNING: When removing fuel filler neck with expansion tank the fuel tank should only be 1/2 full. Drain fuel tank if necessary. However, when loosening hose for filler pipe some fuel may escape. Cut cable tie -1-. (Scheme 101) Disconnect vent line -2-. Loosen hose clamp -3- for filler pipe and pull off filler pipe. Press protection cover away -arrow-. Disconnect vent lines -arrows- at fuel filler neck. (Scheme 102) Remove bolts -1- and -2- for fuel filler neck. Guide vent line -3- to top above fuel filler neck. Remove fuel filler neck together with expansion tank.

Scheme 101

Installation is the reverse of removal, however note the following

Note. Fasten all hose clamps with the same type of clamp that was used in production.

Scheme 102

Scheme 103

1. Check installation position of Ground connection while fuel tank and/or fuel filler neck is removed.
2. Route and connect Ground (GND) wire as shown in Fig. -arrow-.
3. Make sure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
4. Check if contact terminal (tongue) at fastening hole is properly locked in.
5. Hold terminal tongue -1- with bolt -2- for fuel filler neck.

See Caution for connecting Telematics battery under FUEL SUPPLY, ALL WHEEL DRIVE (AWD) .

1. After reconnecting battery, insert anti-theft radio code again. See Radio Owner's Manual .
2. Install right rear wheelhousing liner: See «WHEELHOUSING LINER, REAR»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment__wheelhousing-liner-rear) .
3. Install center and rear muffler stress free. See «EXHAUST SYSTEM - 2.8L V6 AHA, ATQ»(/audi/a6/c5-1997-2001/remont/exhaust/#exhaust-system-emission-controls-28l-v6-aha-atq) .

Note. With Battery re-connected, remember to activate electrical equipment (radio, clock, window switches) according to operating instructions. For further measures after battery voltage is re-connected refer to: See appropriate MULTIPORT FUEL INJECTION (MPI) article.

1. Generate readiness code: See appropriate ON-BOARD DIAGNOSTIC (OBD) article in ENGINE PERFORMANCE.

TIGHTENING TORQUE: FUEL FILLER NECK (VEHICLES WITH 6-CYLINDER ENGINE AND A6 ALLROAD)

Fuel tank with attachments, component overview - vehicles with 8-cylinder engine except A6 Allroad

Note. The fuel filler neck with expansion tank can be exchanged separately. See FUEL FILLER NECK WITH EXPANSION TANK, REMOVING AND INSTALLING - VEHICLES WITH 8-CYLINDER ENGINE EXCEPT A6 ALLROAD .

Note. The following list refers to items in (Scheme 105).

1. Bolt M8 x 28 with attached washer 23 Nm (17 ft lb)
2. Speed nut For heat shield Must be securely fastened
3. Carrier panel
4. Vent line Front part To Evaporative Emissions (EVAP) canister purge regulator valve -N80- Attached to upper part of fuel tank Remains attached when removing tank
5. Fuel return line From fuel filter To fuel sender
6. Fuel supply line From fuel filter To fuel rail Mark before removing Observe direction of arrow at closing flange Attach to fuel tank right front
7. 2 Nm (18 in. lb)
8. Heat shield For fuel filler neck
9. Bolt M8 x 28 with attached washer 23 Nm (17 ft lb)
10. Spring nut 1.3 Nm (11.5 in. lb)
11. Overflow hose
12. Rubber cup
13. Retaining ring
14. Seal Replace if damaged
15. Fuel filler cap Using safety device, hang cap on fuel tank flap.
16. Ground (GND) wire To deter static electricity. Installation position/Checking procedure, see «INSTALLATION POSITION OF GROUND WIRE»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Make sure tight fit of connector and mount terminal with bolt item -9- for fuel filler neck. After installing, measure resistance using multimeter (Fluke 83 or equivalent) between metal ring of fuel filler neck and bare metal part of body. Specified value: approx. 0 ohm CAUTION: After installing, measure resistance using multimeter (Fluke 83 or equivalent) between metal ring of fuel filler neck and bare metal part of body. Specified value: approx. 0 ohm
17. Fuel filler neck with expansion tank Can be replaced separately. See «FUEL FILLER NECK WITH EXPANSION TANK, REMOVING AND INSTALLING - VEHICLES WITH 8-CYLINDER ENGINE EXCEPT A6 ALLROAD»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
18. Vent line Rear part To EVAP canister Attach to top of fuel tank Remains attached to fuel tank during while removing fuel tank
19. Vent line From fuel filler neck to EVAP canister
20. Heat shield For fuel tank
21. 2 Nm (18 in. lb)
22. Fuel tank Removing and installing, see «FUEL TANK WITH ATTACHMENTS, REMOVING AND INSTALLING - VEHICLES WITH 8-CYLINDER ENGINE EXCEPT A6 ALLROAD»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-tank-with-attachments-removing-and)
23. Heat shield For fuel tank
24. Fuel tank support strap Observe installation position

Scheme 104

Note. Check installation position with fuel tank or fuel filler neck removed

Scheme 105

Scheme 106

1. If necessary unbolt expansion tank -1- -arrows-.
2. Route and connect Ground wire as shown -arrow-.
3. Ensure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
4. Check if contact terminal (tongue) at fastening hole is properly locked in.
5. Hold terminal tongue -1- with bolt -2- for fuel filler neck.

Scheme 107

1. A - Procedure on fuel tank more than 1/4 full, see «A - PROCEDURE ON FUEL TANK MORE THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. B - Procedure on fuel tank less than 1/4 full, see «B - PROCEDURE ON FUEL TANK LESS THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__b-procedure-on-fuel-tank) .

Scheme 108

Scheme 109

1. 2012 A
2. VAS 5190

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .
3. Obtain code on vehicles with coded radio/integrated radio.

Audi A6

Scheme 110

1. Remove cover above battery -arrow-.

Note. On vehicles without separate battery cover: Remove plenum cover.

See Caution before beginning repairs on the electrical system. See FUEL SUPPLY, ALL WHEEL DRIVE (AWD) .

1. With ignition switched off, disconnect battery Ground (GND) cable -arrow-.

Audi RS6

Scheme 111

Scheme 112

Scheme 113

1. Switch ignition off and remove the ignition key.
2. Turn locks -arrow- counterclockwise and remove cover -1
3. Remove cover -1- off upward.
4. Connect Ground wire (GND) to battery.

All

A - Procedure on fuel tank more than 1/4 full , see A - PROCEDURE ON FUEL TANK MORE THAN 1/4 FULL .

Scheme 114

Scheme 115

1. Remove cone piece -2- from hose -1- of the VAS 5190.
2. Mark location on hose -arrow- with a piece of insulating tape. a = 1205 mm
3. Remove fuel cap from filler neck.
4. Install hose -1- of VAS 5190 to filler neck of the fuel tank.
5. Push suction hose into fuel tank up to marking tape -arrow-. NOTE: Only push the suction hose up to the marking tape so that the fuel sender is not damaged.
6. Empty fuel tank.
7. Carefully remove suction hose
8. Remove the fuel sender and sealing ring. See «B - PROCEDURE ON FUEL TANK LESS THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__b-procedure-on-fuel-tank) .
9. Suction the remaining fuel out of both right and left fuel tanks.

Note. The Suction device can be used in the same manner without the hose. Mark location on hose -arrow- with a piece of insulating tape. a = 1140 mm The suction hose -1- is installed completely when marking tape is at the edge of the fuel filler neck. If installation of suction hose is difficult, lightly coat hose with engine oil. Under no circumstances should silicone lubricants be used!

Limosine

1. Remove cover for sender for fuel gauge located under liner in luggage compartment.

Avant

1. Remove luggage compartment floor covering

See CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING or CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING .

All

Scheme 116

Scheme 117

Scheme 118

Scheme 119

1. If necessary; fold the left rear seat back forward.
2. Remove cover -arrow- for fuel tank sender.
3. Carefully release 2-pin connector -arrow- and disconnect
4. Remove union nut with wrench 2012 A.
5. Pull fuel supply sensor 3 together with seal out of fuel tank opening.
6. Draw off remaining fuel in left and right chambers of fuel tank through opening for sensor unit.
7. Re-install fuel supply sensor 3 with seal. See «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Fuel tank with attachments, removing and installing - vehicles with 8-cylinder engine except A6 allroad

1. VAG 1383 A Engine/transmission jack with VAG1359/2 Universal support

Scheme 120

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) . For weight reasons the fuel tank must be empty. If necessary empty fuel tank. See «A - PROCEDURE ON FUEL TANK MORE THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Audi A6

Scheme 121

1. Remove cover above battery -arrow-. NOTE: On vehicles without separate battery cover: Remove plenum cover.
2. With ignition switched off, disconnect battery Ground (GND) cable -arrow-.

Scheme 122

Audi RS6

1. Turn locks -arrow- counterclockwise and remove cover -1
2. Remove cover -1- off upward.

See Caution before beginning repairs on the electrical system. See FUEL SUPPLY, ALL WHEEL DRIVE (AWD) .

Scheme 123

1. With ignition switched off, disconnect battery Ground (GND) cable -arrow-.

Scheme 124

All

Scheme 125

Scheme 126

Scheme 127

Scheme 128

Scheme 129

1. Remove rear seat bench. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames) .
2. Remove cover for flange on fuel tank under rear seat bench (right side).
3. Carefully release 4-pin connector -arrow- and disconnect.
4. Thoroughly clean area around fuel filler neck.
5. With the fuel filler flap open, loop -1- where available.
6. Pry locking collar -arrow- in the rubber cup (around the filler neck) out
7. Push rubber cup inward.
8. Open fuel filler cap briefly and close again NOTE: Do not remove caps.
9. Remove center and rear muffler See. «EXHAUST SYSTEM COMPONENTS, REMOVING AND INSTALLING»(ref-196262-S41304031352005100700000) .
10. Remove heat shield for fuel filler neck above rear silencer (right side) -arrow-.
11. Remove rear axle: See appropriate REAR SUSPENSION article.
12. Remove rear right wheel housing liner: See «WHEELHOUSING LINER, REAR»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment__wheelhousing-liner-rear) .
13. Remove bolts -1- and -2- as well as nut -3- for fuel filler neck beneath wheelhousing liner.
14. Remove cover for EVAP canister under spare wheel molding.
15. Remove vent lines -arrows- on EVAP canister

Scheme 130

Vehicles with 8-cylinder (Naturally aspirated engine)

1. Mark supply line -3-, return line -2- and vent line -1- and disconnect.

Scheme 131

Vehicles with 8-cylinder (Turbo engine)

1. Disconnect the fuel advance line -3- from junction point.
2. Disconnect the fuel return pipe -2- and the breather pipe -1-.

Scheme 132

All

Note. The vent line remains attached during removal of fuel tank.

Scheme 133

1. Remove heat shields at left and right of fuel tank.
2. Support fuel tank using VAG1383A engine/transmission jack. WARNING: For weight reason the fuel tank must be empty before removal of the tank is started.
3. Remove fasteners -1- through -8- for support straps and carrier panel.
4. Lower fuel tank together with carrier panel -9-. NOTE: -Arrow- points toward the front of the vehicle.

Installation is the reverse of removal, however note the following

Note. Fasten all hose clamps with the same type of clamp that was used in production. See Parts catalog. Use VAG1921 pliers or similar tool to install spring clamps. Always replace seals and O-rings.

Scheme 134

Scheme 135

1. Check installation position of Ground (GND) connection while fuel tank and/or fuel filler neck is removed. If necessary unbolt expansion tank -1- -arrows-.
2. Route and connect Ground wire as shown -arrow-.
3. Make sure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
4. Check if contact terminal (tongue) at fastening hole is properly locked in.
5. Mount terminal tongue -1- with the bolt -2- for fuel filler neck.

Scheme 136

1. Make sure that fuel supply, return and vent lines at right-front of fuel tank are properly installed in retainers.
2. Carefully install cover for closing flange with indentation positioned on top of connector.

See Caution for connecting Telematics battery. See FUEL SUPPLY, ALL WHEEL DRIVE (AWD) .

1. With ignition switched off, reconnect battery Ground (GND) strap.
2. After reconnecting battery, insert anti-theft radio code again. See Radio Owner's Manual .
3. Using switches, fully close power windows up to stop.
4. Then, operate all power windows for at least 1 second in "close" position to activate "one touch" opening/closing function.
5. Set time display on clock.
6. Install right rear wheelhousing liner: See «WHEELHOUSING LINER, REAR»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment__wheelhousing-liner-rear) .
7. Install center and rear muffler stress free. See «EXHAUST SYSTEM, ALIGNING TO RELIEVE STRESS»(ref-196262-S01228159162005100700000) .
8. Install rear axle: See appropriate REAR SUSPENSION article.
9. Generate readiness code: See appropriate ON-BOARD DIAGNOSTIC (OBD) article in ENGINE PERFORMANCE.

Scheme 137

Fuel filler neck with expansion tank, component overview - vehicles with 8-cylinder engine except A6 Allroad

Note. The following list refers to items in (Scheme 140).

1. Heat shield For fuel filler neck
2. Vent line To EVAP canister
3. Hose connection For fuel filler pipe
4. Vent line To fuel tank front top right
5. Vent line From fuel tank front left
6. Vent line From fuel tank left rear
7. Vent line From fuel tank right rear
8. Ground (GND) wire To deter static electricity. Installation position/Checking procedure, see «INSTALLATION POSITION OF GROUND WIRE»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Make sure tight fit of connector and fasten wire with bolt for fuel filler neck -item 16 -. After installing, measure resistance using multimeter (Fluke 83 or equivalent) between metal ring of fuel filler neck and bare metal part of body. Specified value: approx. 0 ohm CAUTION: After installing, measure the resistance using a multimeter (Fluke 83 or equivalent) between the metal ring of the fuel filler neck and a bare metal part of the body. Specified value: approx. 0 ohm
9. Rubber cup
10. Retaining ring
11. Seal insert For gas station fuel nozzle Replace if damaged Removing and installing, see «SEAL INSERT FOR GAS STATION FUEL NOZZLE, REMOVING AND INSTALLING - ALL ENGINES»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines)
12. Seal Replace if damaged
13. Fuel filler cap
14. Spring nut-1.3 Nm
15. Fuel filler neck with expansion tank With valves and hoses Must be replaced as complete unit Removing and installing, see «FUEL FILLER NECK WITH EXPANSION TANK, REMOVING AND INSTALLING - VEHICLES WITH 8-CYLINDER ENGINE EXCEPT A6 ALLROAD»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
16. Bolts M8 x 30 with attached washer 23 Nm (17 ft lb)
17. Bolts M8 x 30 with attached washer 23 Nm (17 ft lb)
18. Plastic nut-2 Nm

Scheme 138

Note. Check installation position with fuel tank or fuel filler neck removed

Scheme 139

Scheme 140

1. If necessary unbolt expansion tank -1- -arrows
2. Route and connect Ground wire as shown -arrow-.
3. Ensure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
4. Check if contact terminal (tongue) at fastening hole is properly locked in.
5. Hold terminal tongue -1- with bolt -2- for fuel filler neck.

Scheme 141

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) . For removing the filler neck with expansion tank, the fuel tank should not be over 1/2 full. If necessary, empty fuel tank. Refer to «A - PROCEDURE ON FUEL TANK MORE THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . CAUTION: After reconnecting vehicle battery on vehicles equipped with Audi Telematics by OnStar(R), switch-on the emergency (back-up) battery for the Telematic/Telephone Control Module. See «EMERGENCY BATTERY, SWITCHING OFF/ON»(/audi/a6/c5-1997-2001/remont/communication-devices/#radio-telephone-navigation-trip-computer__emergency-battery-switching-offon) .
3. Vehicles with coded radio/navigation system (RNS) coding, Refer to vehicle owner's manual if necessary.

Audi A6

1. Remove cover above battery -arrow-.

Note. On vehicles without battery cover: Remove plenum cover

See Caution before beginning repairs on the electrical system. See FUEL SUPPLY, ALL WHEEL DRIVE (AWD) .

Scheme 142

1. With ignition switched off disconnect battery Ground strap -arrow-.

Scheme 143

Audi RS6

1. Turn locks -arrow- counterclockwise and remove cover -1
2. Remove cover -1- off upward.
3. With ignition switched off, disconnect battery Ground (GND) cable -arrow-.

Scheme 144

All

Scheme 145

Scheme 146

1. Thoroughly clean area around fuel filler neck.
2. With the fuel filler flap open, loop -1- where available.
3. Pry locking collar -arrow- in the rubber cup (around the filler neck) out
4. Push rubber cup inward.
5. Open fuel filler cap briefly and close again
6. Remove heat shield for fuel filler neck above rear muffler -arrows-. NOTE: For easy access lift rear muffler out of hanger.
7. Remove right-rear wheelhousing liner. See «WHEELHOUSING LINERS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment) .
8. Remove right rear wheel.

Note. To ease repair process, remove muffler from muffler hangers.

1. Remove cover for EVAP canister below spare wheel molding.
2. Remove vent line -arrow- from EVAP canister.

Scheme 147

Scheme 148

Scheme 149

Scheme 150

1. Cut cable tie -2-. (Scheme 151)
2. Remove vent line -3-.
3. Loosen hose clamp -1- for filler pipe and detach filler pipe.
4. Remove bolts -1- and -2- as well as nut -3- for fuel filler neck. (Scheme 152)
5. Swing fuel filler neck little toward front of vehicle. CAUTION: DO NOT kink lines.
6. Disconnect vent lines -arrows- at back side of fuel filler neck.
7. Remove fuel filler neck together with expansion tank.

Installation is the reverse of removal, however note the following

Note. Fasten all hose clamps with the same type of clamp that was used in production.

Scheme 151

Scheme 152

Scheme 153

1. Check installation position of Ground connection while fuel tank and/or fuel filler neck is removed. If necessary unbolt expansion tank -1- -arrow-.
2. Route and connect Ground (GND) wire as shown in Fig. -arrow-.
3. Ensure that harness connector for Ground (GND) connection is properly seated on metal ring (Ground clamp) on fuel filler neck.
4. Check if contact terminal (tongue) at fastening hole is properly locked in.
5. Hold terminal tongue -1- with bolt -2- for fuel filler neck.

See Caution for connecting Telematics battery under FUEL SUPPLY, ALL WHEEL DRIVE (AWD) .

1. Install right rear wheelhousing liner: See «WHEELHOUSING LINERS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment) .
2. Install center and rear muffler stress free. See «EXHAUST SYSTEM, ALIGNING TO RELIEVE STRESS»(ref-196262-S01228159162005100700000) . NOTE: With Battery re-connected, remember to activate electrical equipment (radio, clock, window switches) according to operating instructions. For further measures after battery voltage is re-connected refer to: See appropriate MULTIPORT FUEL INJECTION (MFI) article. Generate readiness code: For engine codes ART and AWN, see «READINESS CODE, GENERATING»(ref-216427-S09406351032006012100000) . For engine code BBD, see «READINESS CODE, GENERATING»(ref-216392-S31450259882006012100000) .

Scheme 154

Scheme 155

Scheme 156

1. 3332 Pressure piece
2. 3438 Hook

Scheme 157

1. Thoroughly clean area around fuel filler neck.
2. Remove fuel cap from filler neck.
3. Insert 3438 hook into left-inner hole of seal insert. NOTE: If 3438 hook is not available, use a locally manufactured hook.
4. Release both tabs -arrows- using thin screwdriver.
5. Pull out insert using hook.

1. Press in seal insert using 3322 mandrel until tabs engage. Installation position: tab slots are on top and bottom.

Fuel pump module with sender for fuel gauge, component overview - all engines

Part I

Note. The following list refers to items in (Scheme 161).

1. Fuel supply line From distributor connector to pump in lower accumulator unit Is part of accumulator Not available as replacement part Install at distributor connector item 3
2. Accumulator Houses pump Located on right side of tank
3. Distributor connector Located on right side of tank Secured with 3 tabs in accumulator To remove, push toward left to release tabs and pry to top When installing, attach fuel line to accumulator Different versions
4. Wiring harness (inside fuel tank) From sender for fuel gauge -G- to fuel level sensor 2 Secured with 2 tie-wraps (item -6-) to suction pump lines
5. Sender for fuel gauge - G- Located on right side of tank With tabs installed to accumulator Checking resistance, see «SENDER FOR FUEL GAUGE, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Removing and installing, see «SENDER FOR FUEL GAUGE -G-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__sender-for-fuel-gauge-g-removing)
6. Cable tie Fuel resistant
7. Closing ring Remove and install using 3087 wrench 145 Nm (106 ft lb)
8. Seal Always replace Install dry into fuel tank opening
9. Fuel level sensor 2 -G169- Located on right side of tank Checking resistance, see «SENDER FOR FUEL GAUGE, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Removing, see «FUEL LEVEL SENSOR 2 -G169-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-level-sensor-2-g169-removing) Before removing drain fuel tank
10. Suction jet pump With fuel lines Attached to fuel level sensor 2 Different versions See «FUNCTION»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Checking, see «SUCTION JET PUMP WITH DISTRIBUTOR CONNECTOR, CHECKING - VEHICLES WITH 6-CYLINDER NATURALLY ASPIRATED ENGINE»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Removing and installing, see «SUCTION JET PUMP WITH DISTRIBUTOR CONNECTOR, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines)

Scheme 158

Component overview fuel sender with fuel pump -G6- all engines

Note. The following list refers to items in (Scheme 162).

1. Distributor connector Fastened with 3 tabs to accumulator To remove, move toward left to disengage tabs When installing, attach fuel hose to accumulator When removing fuel pump module, remove distributor connector to make it possible to remove return line from closing flange Different versions
2. Accumulator With pump
3. Wiring inside tank To fuel level sensor 2 -G169- Install at closing flange
4. Electrical wire To sender for fuel gauge -G- Install at closing flange
5. Harness connector For fuel pump and all senders for fuel gauges To release harness connector, see «RELEASE HARNESS CONNECTOR»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__release-harness-connector) .
6. Fuel return line Attached to front part of fuel tank Mark line before removing
7. Fuel pressure line To fuel filter Attached to front part of fuel tank Mark line before removing
8. Closing ring Remove and install using 3087 wrench 145 Nm (106 ft lb)
9. Seal Replace if necessary Install dry into fuel tank opening
10. Closing flange For fuel delivery module Not available as replacement part Note arrow markings when installing
11. Fuel pump module with Fuel Pump -G6- Different versions, See Parts catalog Only replaceable with catch flange Checking fuel pump, see «FUEL PUMP, CHECKING ELECTRICALLY»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Checking fuel pump on vehicles with 8-cylinder-Turbo engine, see «FUEL PUMP (FP) -G6-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Checking, see «FUEL PUMP DELIVERY VOLUME, CHECKING - VEHICLES WITH 6-CYLINDER NATURALLY ASPIRATED ENGINE»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Checking on vehicles with 8-cylinder Turbo engine, see «FUEL PUMP DELIVERY RATE, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Pressure checking: See appropriate MULTIPORT FUEL INJECTION (MFI) article.
12. O-rings Always replace Check installation position
13. Fuel return line To remove fuel pump module, disengage distributor connector and disconnect return line at distributor connector - item 1 - while pressing fastening tabs
14. Fuel filter screen Cannot be replaced as single part Clean if dirty

Scheme 159

Release harness connector

1. Before disconnecting harness connector at fuel pump delivery module, release harness connector. This can be done by hand or using a screw driver -arrow

Scheme 160

Scheme 161

1. 3307 fuel pump wrench
2. VAG1348/3-2 with
3. VAG1348/3A
4. VAG1526 A
5. VAG1594 A

Scheme 162

Scheme 163

1. Battery fully charged (at least 12 volts)
2. Fuse S228 OK (socket 28)
3. Relay in position -4- in relay panel behind storage shelf OK
4. Fuel filter in good condition
5. Ignition switched off

Scheme 164

Scheme 165

Scheme 166

Scheme 167

Scheme 168

Scheme 169

Scheme 170

1. Open cover for fuse panel on driver's side under instrument panel.
2. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
3. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 (arrow).
4. Connect test probe to Battery Positive Voltage (B +).
5. Press remote switch. Fuel pump must run (pump will be audible) NOTE: The pump is very quiet, make sure area is quiet while testing. If the fuel pump does not run
6. Remove rear seat bench. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames) .
7. Remove screws -arrows- for the cover.
8. Carefully release 4-pin harness connector -arrow- and disconnect.
9. Set multimeter (Fluke 83 or equivalent) to 20 volt DC range. Using adapter wire from VW1594 connector test kit connect to terminals -1- and -4- of harness connector.
10. Press (and hold) remote switch and read voltage. Specified value: approx. Battery Positive Voltage (B +) If the specified value is attained but the fuel pump does not run: WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
11. Mark fuel supply line -1- and return line -2- and disconnect from closing flange (right side). WARNING: The closing flange should only be opened if the fuel tank is maximum 1/4 full. Otherwise large quantities of fuel escape. Drain fuel tank if necessary. For procedure, see «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (6-cylinder engine and A6 Allroad) or «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (8-cylinder engine, except A6 Allroad).
12. Remove closing ring for sender for fuel gauge using 3087 wrench.
13. Remove closing flange with seal from tank opening.
14. Make sure electrical connection between flange and fuel pump is good. Check for open circuit. If there are no open circuits
15. Replace fuel pump delivery module. See «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
16. Install fuel pump delivery module. See «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Test requirements

1. VAG1348/3A with VAG1348/3-2 and Container (fuel resistant)
2. Container (fuel resistant)

Scheme 171

1. Battery fully charged (at least 12 volts)
2. Fuel filter OK
3. Ignition switched off

Scheme 172

Scheme 173

Scheme 174

Scheme 175

1. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 arrow-.
2. Open cover for fuse panel on driver's side under instrument panel.
3. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
4. Connect test probe to Battery Positive Voltage (B +).
5. Remove fuel filler cap.
6. Remove engine cover -arrows-. WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
7. Disconnect fuel return line from fuel rail and use rag to catch escaping fuel.
8. Connect test hose -arrow- and hold end of hose in measuring container.
9. Operate remote control for 15 seconds (keep button pressed).
10. Compare the quantity of fuel delivered with specification.
11. Minimum delivery cm 3/15 seconds
12. Voltage at fuel pump with engine stationary and pump running (approx. 2 volts less than battery voltage).

Scheme 176

1. VAG1348/3A with VAG1348/3-2 and Container (fuel resistant)
2. Container (fuel resistent)

1. Battery fully charged (at least 12 volts)
2. Fuel filter OK
3. Ignition switched off

Scheme 177

Scheme 178

Scheme 179

Scheme 180

1. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 -arrow-.
2. Open cover for fuse panel on driver's side under instrument panel.
3. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
4. Remove fuel filler cap.
5. Remove engine cover -A- -arrows-. WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release pressure by slowly separating the connection.
6. Disconnect fuel return line from fuel rail and use rag to catch escaping fuel.
7. Connect test hose -arrow- and hold end of hose in measuring container.
8. Operate remote control for 15 seconds (keep button pressed).
9. Compare the quantity of fuel delivered with specification. *) Minimum delivery cm3/15 seconds **) Voltage at fuel pump with engine stationary and pump running (approx. 2 volts less than battery voltage).
10. Install the fuel return pipe with new hose clip.

1. VAG1348/3A with VAG1348/3-2
2. Container (fuel resistant)

Scheme 181

1. Battery fully charged (at least 12 volts)
2. Fuel filter OK
3. Ignition switched off

Scheme 182

Scheme 183

Scheme 184

Scheme 185

1. Open cover for fuse panel on driver's side under instrument panel.
2. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
3. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 -arrow-.
4. Connect test probe to Battery Positive Voltage (B +).
5. Remove fuel filler cap.
6. Remove engine cover -arrows-. WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release pressure by slowly separating the connection.
7. Disconnect fuel return line from fuel rail and use rag to catch escaping fuel.
8. Connect test hose -arrow- and hold end of hose in measuring container.
9. Operate remote control for 15 seconds (keep button pressed).
10. Compare the quantity of fuel delivered with specification. *) Minimum delivery cm 3/15 seconds **) Voltage at fuel pump with engine stationary and pump running (approx. 2 volts less than battery voltage).
11. Install the fuel return pipe with new hose clip

1. VAG1348/3A with VAG1348/3-2
2. Container (fuel resistant)

Scheme 186

1. Battery fully charged (at least 12 volts)
2. Fuel tank filled at least 1/4 full min.
3. Fuel filter OK
4. Ignition switched off

Scheme 187

Scheme 188

Scheme 189

1. Open cover for fuse panel on driver's side under instrument panel.
2. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
3. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 -arrow-.
4. Connect test probe to Battery Positive Voltage (B +).
5. Remove fuel filler cap.
6. Remove fuel return hose from line adapter
7. Attach auxillary hose to the distribution pipe and insert into container
8. Operate remote maintenance for 15 seconds with the button depressed.
9. Compare amount of fuel with the desired value. *) Minimum delivery cm3/15 seconds **) Voltage at fuel pump with engine stationary and pump running (approx. 2 volts less than battery voltage).
10. Install the fuel return pipe with new hose clip.

1. 3087 Wrench
2. 3307 Fuel Pump Wrench
3. T40020 Unlocking Tool

Scheme 190

Scheme 191

1. Observe safety precautions. See «SAFETY PRECAUTIONS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__safety-precautions) .
2. Observe rules of cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) . For the removal of the fuel sender the fuel tank should be a maximum 1/4 full. Drain fuel tank if necessary. For procedure, see «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (6-cylinder engine and A6 Allroad) or «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (8-cylinder engine except A6 Allroad). CAUTION: After reconnecting vehicle battery on vehicles equipped with Audi Telematics by OnStar (R) switch-on the emergency (back-up) battery for the Telematic/Telephone Control Module. See «EMERGENCY BATTERY, SWITCHING OFF/ON»(/audi/a6/c5-1997-2001/remont/communication-devices/#radio-telephone-navigation-trip-computer__emergency-battery-switching-offon) .
3. Vehicles with coded radio/navigation system (RNS) coding, Refer to owner's manual if necessary. Audi A6
4. Remove cover above battery -arrows-. NOTE: On vehicles without battery cover: Remove plenum cover. See Caution for disconnecting Telematics battery. See «FUEL SUPPLY, ALL WHEEL DRIVE (AWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-all-wheel-drive-awd) .
5. Disconnect battery Ground (GND) strap -arrow- with ignition switched off.

Audi RS6

Scheme 192

Scheme 193

Scheme 194

1. Turn locks -arrow- counterclockwise and remove cover -1
2. Remove cover -1- off upward.
3. With ignition switched off, disconnect battery Ground (GND) cable -arrow-.

All

Scheme 195

Scheme 196

Scheme 197

Scheme 198

Scheme 199

Scheme 200

Scheme 201

Scheme 202

1. Open fuel filler cap briefly and close again
2. Remove rear seat bench. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames).
3. Remove screws for the cover.
4. Carefully release 4-pin harness connector and disconnect. WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release pressure by slowly separating the connection.
5. Mark fuel supply line -1- and return line -2- and disconnect from closing flange (right side). WARNING: The closing flange should only be opened if the fuel tank is maximum 1/4 full. Otherwise large quantities of fuel escape. Drain fuel tank if necessary. For procedure, see «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (6-cylinder engine and A6 Allroad) or «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (8-cylinder engine, except A6 Allroad).
6. Remove closing ring for sender for fuel gauge using 3087 wrench.
7. Remove closing flange and seal from tank opening.
8. Disconnect both harness connector for fuel gauge -1- and -2- on inside of closing flange.
9. Disengage distributor connector -1- at lower part of accumulator by pressing distributor connector slightly to left side of vehicle and lift upward -arrow-. (Scheme 202)
10. Release return line -2- from distributor connector and disconnect. NOTE: For better illustration purpose the accumulator is shown without fuel tank.
11. In addition, unlock quick coupling line connector of return pipe with Unblocking Tool T40020.
12. Insert 3307 fuel pump wrench through fuel tank opening into inner part of accumulator.
13. Using 3307 fuel pump wrench, turn fuel pump module approx. 15° to right (to stop). Notch -1- must then align with marking -2- (bayonet lock)
14. Lift out fuel pump together with inner part of accumulator.

Installation is the reverse of removal, however note the following

Note. Replacement hose clamps must be the same type of clamp that was used in production. See Parts catalog.

Scheme 203

Scheme 204

Scheme 205

Scheme 206

Scheme 207

Scheme 208

Scheme 209

Scheme 210

Scheme 211

1. Install fuel pump module into tank with notch -1- on fuel pump module lining up with marking -2- on outside of fuel pump module. It should feel that it is possible to press fuel pump module down.
2. Insert 3307 Fuel Pump Wrench through fuel tank opening and place on accumulator.
3. Using 3307 fuel pump wrench, turn fuel pump module approx. 15° to right (to stop). Notch -1- must then align with marking -3-.
4. Insert solid line -3- and hose -5- in relevant openings of accumulator -6-.
5. Push return line -1- onto distributor connector -4- until hose coupling engages. NOTE: Always use new O-rings -7- for the return line. Lubricate O-rings for return line with fuel or lubricant.
6. Clip solid line -3- into distributor connector -4- while distributor locks into accumulator -6-.
7. Reconnect harness connectors -1- and -2- for fuel gauge to inside of closing flange.
8. Insert new seal for closing flange dry into fuel tank opening.
9. Ensure that wiring for fuel pump -2- and fuel return line -1- is correctly routed when installing closing flange.
10. When installing, turn closing flange in direction of arrow (Scheme 212)
11. Install closing flange into tank opening. Note installation position: Marking on closing flange -1- must align with marking -2- on fuel tank. NOTE: The -arrow- points toward the front of the vehicle.
12. Tighten closing ring to 120 Nm (89 ft lb).
13. Install fuel supply and return lines as previously marked.
14. Install cover for closing flange with indentation over connector. See Caution for connecting Telematics battery under «FUEL SUPPLY, ALL WHEEL DRIVE (AWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-all-wheel-drive-awd). NOTE: With Battery re-connected, remember to activate electrical equipment (radio, clock, window switches) according to operating instructions. For further measures after battery voltage is re-connected refer to: Appropriate MULTIPORT FUEL INJECTION (MFI) article.
15. Generate readiness code: See appropriate ON-BOARD DIAGNOSTIC (OBD) article in ENGINE PERFORMANCE.

TIGHTENING TORQUES: FUEL PUMP MODULE

Function

Vehicles with 8-cylinder-Turbo engine possess 2 fuel pumps: The Fuel pump -G6-, which sucks in large quantities fuel. It supplies the Transfer Fuel Pump -G23-, which is responsible for the fuel pressure.

The voltage supply of the two fuel pumps is made by the Fuel Pump (FP) Control Module -J538-, which switches the heading for tension for both pumps depending upon engine requirement between 10 V and maximally the available of on-board tension. The Fuel Pump (FP) Control Module -J538- is supplied via the Fuel Pump (FP) Relay -J17- with on-board tension and connects these through directly to the pumps or reduced if necessary this tension to 10 V.

In accordance with the following condition the pumps are headed for

1. When engine starts, the fuel pumps -G6- and -G23- are supplied briefly with full on-board tension, in order to guarantee snap pressure build-up.
2. When driving, the fuel pumps -G6 and -G23 being supplied 10 V are operating. With exceeding of an engine fuel consumption of 90 l/h for both pumps, on-board tension are raised. When falling below a fuel consumption of 64,8 l/h the pumps are addressed with 2 seconds of delay and supplied again with 10 V.
3. With engine running, the voltage supply of both pumps takes place for 5 seconds with on-board tension, in order to avoid bubble formation caused by vapor.

Component overview, Transfer Fuel Pump (FP) -G23

Note. Transfer Fuel Pump (FP) -G23-is located on right front side of fuel tank.

Note. The following list refers to items in (Scheme 215).

1. Connector Remove fuel pump.
2. Fuel hose to fuel filter Secure with hose clamps.
3. Spacer
4. 12Nm
5. Holder clamp for Fuel pump Attaches to fuel tank
6. Spacer
7. Absorbtion piece
8. Fuel hose from fuel tank catch flange Secure with hose clamps.
9. Transfer Fuel Pump (FP) -G23- Checking fuel pump, see «TRANSFER FUEL PUMP (FP) -G23-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Check delivery, see «FUEL PUMP DELIVERY RATE, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Removing and Installing, see «TRANSFER FUEL PUMP (FP) -G23-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Check pressure: See «FUEL PRESSURE REGULATOR AND RESIDUAL PRESSURE, CHECKING»(ref-216433-S29159032312006012100000) .

Scheme 212

1. 3087 Wrench
2. V.A.G 1526 A
3. V.A.G 1594 A

Scheme 213

Scheme 214

Scheme 215

1. Battery voltage at least 12.7 V
2. Fuel Pump (FP) Control Module -J538-test. See «FUEL PUMP (FP) CONTROL MODULE -J538-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
3. Safety device S81 (location C) is in the relay support, driver's side behind the driver's side shelf.
4. Fuel pump relay on card location -4- in the central electrical connection behind the shelf driver's side
5. Fuel filter OK
6. Ignition switched off

Scheme 216

Scheme 217

Scheme 218

Scheme 219

Scheme 220

1. Remove rear seat. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames) .
2. Remove catch flange cover -arrows-. Briefly operate starter Operating noise of pump must be audible NOTE: During testing of the fuel pump, avoid any excess noises No audible running noise from fuel pump: Connect the multimeter for voltage measurement to contacts -1- and -4- as shown, using probes and adapters from VAG 1594 A; the connection remains disconnected. NOTE: Connector pin locations have been numbered and are located on rear of connector.
3. Briefly operate starter. Desired value: Briefly (approx. 1 second) approx. battery voltage, then it drops to 10V. If the specified value is not obtained (no voltage at the fuel pump connector)
4. Check control module for fuel pump. See «FUEL PUMP (FP) CONTROL MODULE -J538-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . If specified value is not obtained, although no operating noise is audible from the pump: WARNING: Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
5. Remove fuel advance line -1- and fuel return pipe -2- WARNING: Catch flange can only be opened with the fuel tank at maximum 1/4 full. otherwise, fuel tank must be drained.
6. Remove fuel sender retaining ring with tool 3087 Wrench.
7. Remove catch flange and sealing ring from the opening of the fuel tank
8. Check if the electrical connection between the flange and fuel pump is connected and/or check continuity. If no problem in the lines exist, fuel pump is defective. Replace fuel pump.
9. Installing fuel pump. See «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Observe notice for connecting battery.

1. V.A.G 1526 A
2. V.A.G 1594 A

Scheme 221

Scheme 222

1. Battery voltage at least 12.7 V
2. Fuel Pump (FP) Control Module -J538-; checking, see «FUEL PUMP (FP) CONTROL MODULE -J538-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
3. Safety device S81 OK (card location C) is in the relay support, driver's side behind the driver's side shelf.
4. Fuel pump relay on card location 4 in the central electrical connection behind the driver's side shelf.
5. Fuel filter OK
6. Switch ignition off

1. Briefly operate starter. Vibration of the pump right on fuel tank must be felt.

If no vibration is felt

Scheme 223

Scheme 224

1. Remove screw -3- and pull fuel pump downward. Fuel hoses -2- and -4- as well as connector -1- remain attached.
2. Connect the multimeter for voltage measurement to contacts -1- and -2- as shown, using probes and adapters from VAG 1594 A; the connection remains disconnected.
3. Briefly operate starter Desired value: Briefly (approx. 1 second) approx. battery voltage, then it drops to 10V.

Desired value is reached, although no vibration at the pump is felt

1. Replace defective fuel pump. See «COMPONENT OVERVIEW, TRANSFER FUEL PUMP (FP) -G23»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__component-overview-transfer-fuel-pump-fp) .

Desired value is not reached

1. Check circuit between Fuel Pump (FP) Control Module -J538- and Transfer Fuel Pump (FP) -G23- using circuit diagram.

No wiring problem found

1. Checking Fuel Pump (FP) Control Module -J538-. See «FUEL PUMP (FP) CONTROL MODULE -J538-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

1. V.A.G 1526 A
2. V.A.G 1594 A
3. V.A.G 1598/31
4. VAS 5051 with VAS 5051/5a

Scheme 225

Scheme 226

Scheme 227

1. Battery voltage at least 12.7 V.
2. Safety device S81 OK (card location C) is in the relay support, driver's side behind the driver's side shelf.
3. Fuel pump relay on card location 4 in the central electrical connection behind the driver's side shelf.
4. Switch ignition off.

1. Remove the right rear airbag. See appropriate AIR BAG article in RESTRAINTS.
2. Remove foam material block from the cavity under the right rear seat belt fastener.

Scheme 228

Scheme 229

1. Disconnect connector -4- for Fuel Pump (FP) Control Module -J538- (-2-).
2. Connect the multimeter for voltage measurement as specified below. VOLTAGE MEASUREMENT: FUEL PUMP CONTROL MODULE Connector terminal Desired value 2 Engine ground
3. Connect VAS 5051 and select "01 - engine electronics". Switch ignition on. See «ON BOARD DIAGNOSTIC (OBD) - 4.2L V8 5V - ART, AWN»(ref-216427) or «ON BOARD DIAGNOSTIC (OBD) - 4.2L V8 5V - BBD»(ref-216392) .

VAS 5051

Scheme 230

1. Select diagnostic function -1- "03 - control module diagnosis".

VAS 5051

A - Output check test waiting

Continue as required

1 - Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80

Scheme 231

1. Select right arrow key. Desired value: Battery voltage
2. Quit "03 - control member diagnosis" by selecting left arrow key

Desired value not reached

1. Repair wiring concern using circuit diagram
2. Connect the multimeter for voltage measurement as specified below. VOLTAGE SUPPLY CIRCUIT TEST: FUEL PUMP CONTROL MODULE -J538- Connector terminal Desired value 1 Battery pos. ( + ) Desired value: Battery voltage Desired value not reached
3. Repair wiring concern using circuit diagram.
4. Re-connect connector.

Scheme 232

1. Disconnect connector -3- for Fuel Pump (FP) Control Module -J538- -2 -. NOTE: Connectors -1- and -4- remain connected.
2. Connect the multimeter for voltage measurement as specified below. ACTIVATION CIRCUIT TEST: FUEL PUMP CONTROL MODULE -J538- Connector terminal Desired value 5 Battery pos. (+)
3. Briefly operate starter Desired value: Briefly (approx. 1 second) approx. battery voltage, then it drops to 10V.

Desired value not reached

Scheme 233

Scheme 234

1. Connect test box VAG1598/31 to the circuit harness connector; do not connect the ECM. Connect the ground clip of the test box to ground (not shown in illustration). See «WIRING AND COMPONENTS, CHECKING WITH VAG 1598/31 TEST BOX»(ref-216428-S21370730362006012100000) (4.2L V8 ART, AWN), or «WIRING AND COMPONENT CHECK WITH TEST BOX VAG 1598/31»(ref-216393-S24182001112006012100000) (4.2L BBD). WARNING: To avoid damaging electrical components, select the appropriate measurement settings on the measuring device before connecting to the components.
2. Check following line connection for interruption and short-circuit after mass and/or plus: OPEN/SHORT CIRCUIT TEST: FUEL PUMP CONTROL MODULE -J538- Connector terminal Test box V.A.G 1598/22 Socket 5 114
3. Repair short circuit and/or circuit malfunction using circuit diagram

Scheme 235

Scheme 236

1. Connect test box VAG1598/31 to the circuit harness connector; do not connect the ECM. Connect the ground clip of the test box to ground (not shown in illustration). See «WIRING AND COMPONENTS, CHECKING WITH VAG 1598/31 TEST BOX»(ref-216428-S21370730362006012100000) (4.2L V8 ART, AWN), or «WIRING AND COMPONENT CHECK WITH TEST BOX VAG 1598/31»(ref-216393-S24182001112006012100000) (4.2L BBD). WARNING: To avoid damaging electrical components, select the appropriate measurement settings on the measuring device before connecting to the components.
2. Check the following circuit connections for open circuits and shorts to ground and/or battery positive (+): DIAGNOSIS CIRCUIT TEST: FUEL PUMP CONTROL MODULE -J538- Connector terminal Test box VAG 1598/31 Socket 2 74
3. Repair the open circuit and or the short according to the schematics.

Voltage supply for Fuel Pump (FP) -G6- (of the Fuel Pump (FP) Control Module -J538-), checking

Note. Electrical circuits -1- to the fuel pump can not be disconnected from the control module -2-for the fuel pump. This is why the voltage supply is measured directly at the fuel pump.

Scheme 237

1. Remove rear seat. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames) .
2. Remove cover located under rear seat.
3. Briefly operate starter Operating noise of the Fuel Pump (FP) -G6- must be audible at the locking flange (right).

Note. Fuel pump runs very quietly. During the checking of the fuel pump, excess noise should be avoided.

If no operating noise is audible

Scheme 238

1. Connect the multimeter for voltage measurement to contacts 1 and 4 as shown, using probes and adapters from VAG 1594 A; the connection remains disconnected. NOTE: Pin numbers are located on the back of connector.
2. Briefly operate the starter Desired value: Briefly (approx. 1 second) approx. battery voltage, then it drops to 10V. Desired value not reached
3. Check the circuit connection between fuel pump control module -J538- and fuel pump -G6- for open circuits according to the schematics.

No problem found

1. Replace Fuel Pump (FP) Control Module -J538

Scheme 239

Scheme 240

1. Remove screw -3- and pull fuel pump downward; Fuel hoses -2- and -4- and connector -1- remain connected.
2. Connect the multimeter for voltage measurement to contacts 1 and 2 as shown, using probes and adapters from VAG 1594 A; the connection remains disconnected.
3. Briefly operate starter Desired value: Voltage briefly climbs to approx. 12V, then falls to approx. 10V.

Desired value not reached

1. Check wiring between Fuel Pump (FP) Control Module -J538- and Transfer Fuel Pump (FP) -G23- using circuit diagram.

If no error is found

1. Replace Fuel Pump (FP) Control Module -J538-.

TIGHTENING TORQUE: FUEL PUMP RETAINING CLIP

1. VAS 5051
2. Container (fuel resistant)

1. Battery voltage not less than 12 V
2. Fuel tank at least 1/4 full
3. Fuel pump control module -J528- OK. For checking, see «FUEL PUMP (FP) CONTROL MODULE -J538-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
4. Fuel filter OK
5. Ignition switched off

In installed conditions, the Sensor 1 shows approx. 20 OHMS when the fuel tank is empty.

Scheme 241

Scheme 242

Scheme 243

1. Remove air cleaner housing.
2. Block the openings of the air circulation pipe in the back with clean foam pads of -arrows-, so that no small articles can infiltrate system.
3. Remove fuel filler cap. WARNING: Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
4. Remove fuel return hose -1- from the line adapter at the fuel distribution pipe
5. Attach auxiliary hose -arrow- at the fuel distribution pipe and insert into a measuring cup
6. Connect VAS 5051 and select "01 -engine electronics". See «ON BOARD DIAGNOSTIC (OBD) - 4.2L V8 5V - ART, AWN»(ref-216427) . See «ON BOARD DIAGNOSTIC (OBD) - 4.2L V8 5V - BBD»(ref-216392) .
7. Switch ignition on.

VAS 5051

1. Select the diagnostic function -1- "03 -control module diagnosis".

VAS 5051

A - Output check test waiting Continue as required

1 - Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80

Scheme 244

1. Select the diagnostic function -1 - "03 -control module diagnosis" right arrow key

VAS 5051

A - Output check test running

Allowed to continue

Note. During the time that the -N80- is activated, the fuel pump is running on 10V operating voltage.

Scheme 245

1. Quit function "03 - control module diagnosis" after exactly 15 seconds by touching left arrow key.
2. Compare amount of fuel with desired value. Minimum delivery 500 cm3/15 s
3. Install the fuel return pipe with new hose clip.
4. Install the air cleaner housing.
5. Verify the correct installation of the air filter housing: Mass airflow sensors must be completely inserted in the intake tube a = max. 5 mm

Fuel pump (FP) -G6-, removing and installing

Note. In tank fuel pump -G6- of the 8-cylinder Turbo engine is removed in the same manner as other models. For fuel delivery unit, removing and installing, see SUCTION JET PUMP WITH DISTRIBUTOR CONNECTOR, REMOVING AND INSTALLING .

1. Container (fuel resistant)

1. Observe all safety precautions. See «SAFETY PRECAUTIONS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__safety-precautions) .
2. Observe the rules of cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .

Scheme 246

Scheme 247

Scheme 248

1. Vehicles with coded radio/navigation system (RNS) coding, Refer to owner's manual, if necessary.
2. Switch ignition off and remove key.
3. Remove bolts -arrow- from cover -1-.
4. Remove cover upward.
5. Connect ground (GND) wire -arrow- to Battery.
6. Open and close fuel filler cap.
7. Remove screw -3-.
8. Disconnect connector -1-.
9. Attach container for catching fuel. WARNING: Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
10. Remove fuel hoses -2- and -4-.
11. Remove fuel pump with spacer pieces -6-and absorber -5-.

Installation is reverse of removal

Note. Secure all hose connectors with hose clamps, which correspond to the series conditions.

1. Install the dampers (like springs) and the spacers to the new fuel pump.
2. Fasten the pump to the holder.

Note. When reconnecting the battery, the vehicle equipment (radio/Radio-navigation system, clock, power windows) will need to be reprogrammed for activation.

TIGHTENING TORQUE: FUEL PUMP RETAINING CLIP

1. V.A.G 1526 A
2. V.A.G 1594 A

Scheme 249

Scheme 250

Scheme 251

1. Remove rear seat. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames).
2. Unscrew screws -arrow- and remove cover for catch flange.
3. Disconnect connector -arrow
4. Connect the multimeter to contacts 2 and 3. (Scheme 256) FUEL GAUGE SENDER (AWD) RESISTANCE MEASUREMENT Empty Full approx. 70 ohm approx. 270 ohm
5. If the measured value is 0, there is a short. If the measured value is (1) there is an open. NOTE: -G-, -G169-, and -G237- are switched in a row. For that reason all 3 are tested together. To test a single Sender, it must be removed. See «SENDER FOR FUEL GAUGE -G-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__sender-for-fuel-gauge-g-removing), or «FUEL LEVEL SENSOR 2 -G169-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-level-sensor-2-g169-removing), or «FUEL SUPPLY SENSOR 3 -G237-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-sensor-3-g237-removing). To test the resistance value of "Full tank" and/or "Empty tank" swing the float to either the upper end position and/or the lower end position. If a malfunction is suspected, check the resistance value of the installed Sender 3 (dependent on the level) by disconnecting the connector at Sender 2 and measuring resistance at that connector. With sender for fuel gauge or fuel level sensor removed, the following values will result due to the longer reach of the float arm

Vehicles with build date up to approx. 02/99

FLOAT RESISTANCE VALUE (AWD): VEHICLES WITH BUILD DATE UP TO APPROX. 02/99

Note. On vehicles with a build date up to approx. 02/99, if any of the Senders for fuel gauge are found defective, all 3 Senders must be replaced with those for vehicles with later build dates. Connect the multimeter for voltage measurement to contacts 2 and 3.

Vehicles with build date as of approx 02/99

Note. As of the approx build date of 02/99, the resistance value range of Senders II and III were changed. The total resistance value ( FUEL GAUGE SENDER (AWD) RESISTANCE MEASUREMENT ), however, stayed the same.

FLOAT RESISTANCE VALUE (AWD): VEHICLES WITH BUILD DATE AS OF APPROX 02/99

Sender for fuel gauge -G-, removing and installing

1. Observe safety precautions. See «SAFETY PRECAUTIONS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__safety-precautions) .
2. Observe rules of cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .

Scheme 252

1. Removing fuel pump delivery module, see «FUEL PUMP MODULE, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . NOTE: If the fuel pump delivery module is only removed to remove the sender for fuel gauge -G-, the fuel return line and distributor connector do not need to be disconnected. Place fuel pump delivery module beside tank opening.
2. Remove sender from accumulator by pressing down on releases -arrows-. NOTE: For better illustration purpose the accumulator is shown without fuel tank.

Installation is the reverse of removal, however note the following

Scheme 253

1. Insert sender for fuel gauge into guide of outside of accumulator and press down until stop -arrow-.
2. Install fuel pump delivery module. See «INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Observe Note and procedures regarding reconnecting battery.

Finishing steps

1. Fill vehicle with fuel.
2. Checking entire resistance of sender for fuel gauge. See «SENDER FOR FUEL GAUGE, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Specification: approximately 270 ohms (Tank full)

Fuel Level Sensor 2 -G169-, removing and installing

1. Observe safety precautions. See «SAFETY PRECAUTIONS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__safety-precautions) .
2. Observe rules of cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .

1. 3087 Fuel Tank Wrench

Scheme 254

1. For the removal of the fuel sender the fuel tank should be a maximum 1/4 full. Drain fuel tank if necessary. For procedure, see «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (6-cylinder engine and A6 Allroad) or «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (8-cylinder engine except A6 Allroad).

1. Vehicles with coded radio/navigation system (RNS) coding, Refer to owner's manual, if necessary.

Audi A6

Scheme 255

1. Remove cover above battery -arrows-. NOTE: On vehicles without battery cover: Remove plenum cover. See Caution before beginning repairs on the electrical system. See «FUEL SUPPLY, ALL WHEEL DRIVE (AWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-all-wheel-drive-awd) .
2. Disconnect battery Ground (GND) strap -arrow-, with ignition switched off.

Scheme 256

Audi RS6

Scheme 257

Scheme 258

1. Turn locks -arrow- counterclockwise and remove cover -1-.
2. Remove cover -1 - off upward.
3. With ignition switched off, disconnect battery Ground (GND) cable -arrow-.

All

Scheme 259

Scheme 260

Scheme 261

Scheme 262

1. Open fuel filler cap briefly and close again.
2. Remove rear seat bench. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames).
3. Remove screws -arrows- for the cover.
4. Carefully disengage 2-pin harness connector -arrow- and disconnect. (4-pin harness connector (Scheme 265)) WARNING: When removing fuel level sensor 2 the fuel tank should only be 1/4 full. Otherwise large quantities of fuel escape.
5. Remove closing ring (driver side) using 3087 Fuel Tank Wrench.
6. Remove fuel level sensor 2 together with seal slightly out of opening in tank.
7. Disconnect harness connectors for sender for fuel gauge at inside (closing flange) of fuel level sensor 2.
8. Reach into tank and disconnect fuel lines to suction jet pump -2- by releasing tabs -arrows-. NOTE: For better illustration purpose the accumulator is shown without fuel tank.

Installation is the reverse of removal, however note the following

Note. Do not bend the fuel level sensor during installation.

Scheme 263

Scheme 264

Scheme 265

1. Connect harness connectors before installing fuel level sensor 2 into fuel tank.
2. On inside of fuel tank install fuel lines to suction jet pump -2- into fuel level sensor 2. Tabs must engage.
3. Insert new seal for fuel level sensor 2 dry into opening for fuel tank.
4. Consider the installation position of the fuel sender for fuel supply: Marking on fuel sender -2- must match marking on fuel tank -1-.
5. Tighten closing ring with 120 Nm (89 ft lb).
6. Install fuel supply and return lines as previously marked.
7. Install cover for closing flange with indentation over connector. See Caution for connecting Telematics battery. See «FUEL SUPPLY, ALL WHEEL DRIVE (AWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-all-wheel-drive-awd) . NOTE: With Battery re-connected, remember to activate electrical equipment (radio, clock, window switches) according to operating instructions.
8. With ignition switched off, reconnect battery Ground (GND) strap.
9. After reconnecting battery, insert radio code. See Radio Owner's Manual.
10. Generate readiness code: See appropriate ON-BOARD DIAGNOSTIC (OBD) article in ENGINE PERFORMANCE.

Finishing steps

1. Fill vehicle with fuel.
2. Check entire resistance of fuel level sensor 2. See «SENDER FOR FUEL GAUGE, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Specification: approximately 270 ohm (Tank full)

TIGHTENING TORQUES: FUEL PUMP DELIVERY MODULE (AWD)

Fuel Supply Sensor 3 -G237-, removing and installing

1. Observe safety precautions. See «SAFETY PRECAUTIONS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__safety-precautions) .
2. Observe rules of cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .

1. 2012 A Wrench

Scheme 266

1. For removing the filler neck with expansion tank, the fuel tank should not be over 1/4 full. If necessary, empty fuel tank refer to «A - PROCEDURE ON FUEL TANK MORE THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

1. Vehicles with coded radio/navigation system (RNS) coding, Refer to owner's manual, if necessary.

Audi A6

Scheme 267

1. Remove cover above battery -arrows-. NOTE: On vehicles without battery cover: Remove plenum cover. See Caution before beginning repairs on the electrical system under «FUEL SUPPLY, ALL WHEEL DRIVE (AWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-all-wheel-drive-awd) .
2. Disconnect battery Ground (GND) strap -arrow-, with ignition switched off.

Scheme 268

Scheme 269

1. Switch off ignition and remove ignition key.
2. Turn locks -arrow- counterclockwise and remove cover-1
3. Remove cover -1 - off upward.
4. Connect the ground wire to battery -arrow-.

Scheme 270

1. Briefly open and close fuel tank cap.

Limosine

1. Remove cover for sender for fuel gauge located under liner in luggage compartment.

Avant

1. Remove cover for sender for fuel gauge located under liner luggage compartment. See «CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) or «CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) .

Scheme 271

Scheme 272

Scheme 273

1. If necessary; fold the left or right rear seat back forward.
2. Remove cover -arrow- for fuel tank sender. WARNING: When removing fuel supply sensor 3 the fuel tank should only be 3/4 full. Drain fuel tank if necessary. For procedure, see «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (6-cylinder engine and A6 Allroad) or «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (8-cylinder engine except A6 Allroad).
3. Remove cover for closing flange under luggage compartment lining. NOTE: On Avant models remove luggage compartment lining. See «CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) or «CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/exteriorinterior-trim/#interior-trim__cargo-area-floor-trim-and-supports) .
4. Carefully disengage 2-pin harness connector -arrow-and disconnect. WARNING: When removing fuel supply sensor 3 the fuel tank should only be 3/4 full. Otherwise large quantities of fuel escape.
5. Remove union nut using 2012 wrench.
6. Pull fuel supply sensor 3 from opening in tank.

Installation is the reverse of removal, however note the following

Scheme 274

Scheme 275

1. Insert fuel supply sensor 3 (Scheme 2) into fuel tank as shown in illustration. The float -1 - shows to top left. NOTE: The -arrow- shows toward front. The fuel tank is shown in a partial side view.
2. Vehicles with 6 cylinder engine: While inserting turn sensor clockwise on own axle -arrow-. NOTE: Do not bend float arm of sensor.

Illustration shows fuel supply sensor 3 correct installed

1. Float -1 - and arm -2- of sensor shows to front left.

Note. Arrow- shows in driving direction. The fuel tank is shown in a partial side view.

Scheme 276

Scheme 277

Scheme 278

1. Push new seal for fuel supply sensor 3 over closing flange of sensor.
2. Insert seal dry into opening of fuel tank.
3. Note the installation position of fuel supply sensor 3. Marking -2- on fuel supply sensor 3 must align with marking -1- on the fuel tank. NOTE: Arrow-shows in driving direction.
4. Tighten union nut for fuel supply sensor 3.
5. Tightening torque: 30 Nm (22 ft lb). See Caution for connecting Telematics battery under «FUEL SUPPLY, ALL WHEEL DRIVE (AWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-all-wheel-drive-awd) NOTE: With Battery re-connected, remember to activate electrical equipment (radio, clock, window switches) according to operating instructions.
6. Generate readiness code: See appropriate ON-BOARD DIAGNOSTIC (OBD) article in ENGINE PERFORMANCE.

Finishing steps

1. Fill vehicle with fuel.
2. Check entire resistance of fuel supply sensor 3. See «SENDER FOR FUEL GAUGE, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Specification: approximately 270 ohm (Tank full)

TIGHTENING TORQUE: FUEL PUMP DELIVERY MODULE CLOSING RING (AWD)

The fuel tank on vehicles with All Wheel Drive (AWD) employs a multi-chamber (2 chambers) system.

In order to transport the fuel volume from the left chamber to the accumulator-6- of the fuel delivery module in the right chamber, the system uses a so called suction jet pump -8-.

A second suction jet pump -2- is located in the right fuel tank chamber and increases the fuel delivery to the accumulator of the fuel delivery module.

Scheme 279

The suction jet pumps operates after the "Fluid entertainment principle": The jet of fuel from the fuel return line -4-is forced via jets in the suction jet pumps -2- and -8-, and is therefore accelerated. This acceleration sucks the surrounding fuel to the accumulator of the fuel delivery module. The right suction jet pump -2-pumps the fuel directly into the accumulator, the left suction jet pump -8- over a separate line -7-.

The fuel is via the distributor connector-1-distributed to both suction jet pumps. At the same time the distributor regulates the pressure in the lines to the suction jet pumps at approx.: 1 bar (14.7 psi). Excessive fuel is sent via a direct line -5- to the accumulator.

3 - Fuel supply line

Scheme 280

1. VAG1318 with VAG1318/10 and VAG1318/11
2. Remote control VAG1348/3A with adapter cable VAG1348/3-2

Scheme 281

1. Battery voltage not less than 12 V
2. Fuse No. 28 OK
3. Fuel filter OK

Scheme 282

Scheme 283

Scheme 284

Scheme 285

1. Open cover for fuse panel on driver's side under instrument panel.
2. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
3. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 -arrow-.
4. Connect test probe to Battery Positive Voltage (B+).
5. Remove fuel filler cap from fuel filler cap.
6. Engine cover -arrow-. WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
7. Remove fuel return hose from fuel rail.
8. Connect pressure gauge V.A.G 1318 using adapters V.A.G 1318/10 and 1318/11 and extension hose -1- between fuel rail pipe and return hose -2-.
9. Press remote control switch for several seconds and watch reading on pressure gauge. Specification: 0.8 to 1.3 bar If specification not attained or exceeded
10. Replace suction jet pump and distributor connector. See «SUCTION JET PUMP WITH DISTRIBUTOR CONNECTOR, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Scheme 286

1. VAG1318 with VAG1318/10 and VAG1318/11
2. Remote control VAG1348/3A with adapter cable VAG1348/3-2

Scheme 287

1. Battery voltage not less than 12 V
2. Fuse No. 28 OK
3. Fuel filter OK

Scheme 288

Scheme 289

Scheme 290

1. Open cover for fuse panel on driver's side under instrument panel.
2. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
3. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 -arrow-.
4. Connect test probe to Battery Positive Voltage (B+).
5. Remove fuel filler cap from fuel filler cap.
6. Engine cover -arrow-. WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
7. Remove fuel return hose from fuel rail.
8. Connect pressure gauge V.A.G 1318 using adapters V.A.G 1318/10 and 1318/11 and extension hose -1- between fuel rail pipe and return hose -2-.
9. Press remote control switch for several seconds and watch reading on pressure gauge. Specification: 0.8 to 1.3 bar

If specification not attained or exceeded

Scheme 291

1. Replace suction jet pump and distributor connector. See «SUCTION JET PUMP WITH DISTRIBUTOR CONNECTOR, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Scheme 292

1. VAG1318 with VAG1318/10 and VAG1318/11
2. Remote control VAG1348/3A with adapter cable VAG1348/3-2

Scheme 293

1. Battery voltage not less than 12 V
2. Fuse No. 28 OK
3. Fuel filter OK

Scheme 294

Scheme 295

Scheme 296

1. Open cover for fuse panel on driver's side under instrument panel.
2. Remove fuse 28 from relay panel (left-row, fifth large fuse from top).
3. Connect VAG1348/3A remote switch with VAG1348/32 adapter cable to cavity for fuse 28 -arrow-.
4. Connect test probe to Battery Positive Voltage (B+).
5. Remove fuel filler cap from fuel filler cap.
6. Engine cover -arrow-. WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
7. Remove fuel return hose from fuel rail.
8. Connect pressure gauge V.A.G 1318 using adapters V.A.G 1318/10 and 1318/11 and extension hose -1- between fuel rail pipe and return hose -2-.
9. Press remote control switch for several seconds and watch reading on pressure gauge. Specification: 0.8 to 1.3 bar

If specification not attained or exceeded

Scheme 297

1. Replace suction jet pump and distributor connector under «SUCTION JET PUMP WITH DISTRIBUTOR CONNECTOR, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Install fuel return pipe with new hose clip.

1. V.A.G 1318 with V.A.G 1318/10 and V.A.G 1318/11
2. V.A.G 1348/3A with V.A.G 1348/3-2

Test conditions

1. Battery voltage at least 12.7 V
2. Safety device S228 OK. (card location 28)
3. Fuel filter OK

Scheme 298

Scheme 299

Scheme 300

1. Open fuse box cover on left side of the instrument panel.
2. Pull fuse No. S228 off fuse holder (left row, 5th large fuse from top).
3. Connect remote control V.A.G 1348/3A with adapter lead V.A.G 1348/3-2 to right-hand fuse socket of fuse No. 28 -arrow-.
4. Connect clamp to vehicle battery (+).
5. Remove filler cap from fuel tank filler neck. WARNING: Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
6. Remove fuel return hose -2- from the line adapter at the fuel distribution pipe
7. Attach V.A.G 1318 with adapters V.A.G 1318/10 and 1318/11 and an auxiliary hose between fuel distribution pipe -1- and return hose -2-.
8. Press the remote control switch for several seconds and observe the pressure reading. Desired value: 0.8 to 1.3 bar

Desired value is fallen below or

1. Replace the suction jet pump and the distributor connector. See «SUCTION JET PUMP WITH DISTRIBUTOR CONNECTOR, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Install fuel return pipe with new hose clip.

1. V.A.G 1318 with V.A.G 1318/10 and V.A.G 1318/11
2. VAS 5051

1. Battery voltage at least 12.7 V
2. Fuel filter OK
3. Fuel tank should be maximum. 1/4 filled.
4. Fuel Pump (FP) Control Module -J538-, see «FUEL PUMP (FP) CONTROL MODULE -J538-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) for testing.

Scheme 301

Scheme 302

Scheme 303

1. Remove the air cleaner housing.
2. Block the openings of the air circulation pipe in the back with clean foam pads -arrows-, so that no small articles can infiltrate system.
3. Remove the cap from the filler neck. WARNING: Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
4. Remove fuel return hose -1- from the line adapter at the fuel distribution pipe.
5. Connect V.A.G 1318 with adapters V.A.G 1318/10 and 1318/11 and an auxiliary hose between fuel distribution pipe -1- and return hose -2-.
6. With ignition switch "ON", connect VAS 5051 vehicle diagnosis -, measuring and information system and select "01 - engine electronics".

VAS 5051

1. Select -1- for the diagnostic test function "03 - Control Module Diagnosis".

Scheme 304

VAS 5051

A - Output check test waiting

Continue as required

1 - Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80

1. Select the right -arrow- key.

Scheme 305

VAS 5051

A - Output check test running

Allowed to continue

1. Observe the pressure reading. Desired value: 1.4 to 2.0 bar
2. Quit function "03 - control member diagnosis" by touching the -arrow- key.

If the desired value has not been reached

Scheme 306

1. Replace suction jet pump with manifold. See «SUCTION JET PUMP WITH DISTRIBUTOR CONNECTOR, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Install the fuel return pipe with new hose clip.
3. Install air cleaner housing.
4. Check that air filter housing is properly installed Mass airflow sensor must be completely inserted in the intake air pipe. -a- = max. 5 mm

1. 3087 Wrench
2. 3307 Fuel Pump Wrench
3. T40020 Unblocking Tool

Scheme 307

Note. The following describes the removal of the suction jet pump on the left side of the fuel tank. The right suction jet pump is part of the accumulator and cannot be separately replaced.

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe rules for cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) . For removing the filler neck with expansion tank, the fuel tank should not be over 1/4 full. If necessary, empty fuel tank refer to «A - PROCEDURE ON FUEL TANK MORE THAN 1/4 FULL»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . CAUTION: After reconnecting vehicle battery on vehicles equipped with Audi Telematics by OnStar(R)R, switch-on the emergency (back-up) battery for the Telematic/Telephone Control Module. See «EMERGENCY BATTERY, SWITCHING OFF/ON»(/audi/a6/c5-1997-2001/remont/communication-devices/#radio-telephone-navigation-trip-computer__emergency-battery-switching-offon) .
3. Vehicles with coded radio/navigation system (RNS) coding, Refer to owner's manual, if necessary.

Audi A6

Scheme 308

Scheme 309

1. Remove cover above battery -arrow-. NOTE: On vehicles without separate battery cover: Remove plenum cover. See Caution before beginning repairs on the electrical system under «FUEL SUPPLY, ALL WHEEL DRIVE (AWD)»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__fuel-supply-all-wheel-drive-awd) .
2. Disconnect battery Ground (GND) strap -arrow-, with ignition switched off. WARNING: When removing suction jet pump the fuel tank should only be 1/4 full. Drain fuel tank if necessary. For procedure, see «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (6-cylinder engine and A6 Allroad) or «FUEL TANK, DRAINING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) (8-cylinder engine except A6 Allroad).

Audi RS6

Scheme 310

Scheme 311

1. Turn locks -arrow- counterclockwise and remove cover -1-.
2. Remove cover -1- upward.
3. With ignition switched off, disconnect battery Ground (GND) cable -arrow-.

All

Scheme 312

Scheme 313

Scheme 314

Scheme 315

Scheme 316

Scheme 317

Scheme 318

Scheme 319

Scheme 320

Scheme 321

Scheme 322

Scheme 323

Scheme 324

Scheme 325

1. Briefly open and close fuel tank cap.
2. Remove rear seat bench. See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames) .
3. Remove cover for closing flange under rear seat bench, right side.
4. Carefully disengage 2-pin harness connector -arrow- and disconnect. (4-pin harness connector shown). WARNING: Fire Hazard! Do not smoke, work near heaters or have anything in the area that could ignite the fuel or fumes. Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
5. Mark fuel supply line -1- and fuel return line -2- and disconnect from closing flange (right side). WARNING: When removing suction jet pump the fuel tank should only be 1/4 full. Otherwise large quantities of fuel escape.
6. Unbolt closing ring using 3087 Wrench.
7. Remove flange and seal out of opening in fuel tank.
8. Disconnect both connectors -1- and -2- for fuel gauge sender on inside of flange.
9. Insert fuel pump spanner 3307 through opening in fuel tank and apply spanner to inner section of accumulator.
10. Using spanner 3307 turn inner section of accumulator counter-clockwise (approx. 15 degrees). Notch -1- should line up with marking -2-.
11. Remove fuel pump with inner section of accumulator.
12. Pull corrugated hose between accumulator and connecting piece out of accumulator.
13. Press retaining tab, and at the same time pull the sender unit out of accumulator in fuel tank -arrows-. NOTE: For better illustration purpose the accumulator is shown without fuel tank. NOTE: For better illustration purpose the accumulator is shown without fuel tank.
14. Unclip connecting piece -1- from lower section of accumulator. To do this, carefully press connecting piece toward left side of vehicle and lift out -arrow-.
15. Pull return hoses -4 and 5- off connecting piece (release hose connectors).
16. Pull hose -2- out of accumulator.
17. Unclip rigid pipe -3- from connecting piece.
18. In addition, unlock quick coupling line connectors of the return pipes with unlocking tool T40020.
19. Remove cover -arrows- for fuel tank sender.
20. Remove cover for closing flange below rear seat bench (left side).
21. Carefully release 2-pin connector -arrow- on fuel level sensor 2 (left side of vehicle) and disconnect.
22. Unscrew locking ring (left side of vehicle) using spanner for fuel gauge sender unit 3087.
23. Carefully pull fuel level sensor 2 a short distance out of fuel tank opening together with seal.
24. Disconnect harness connector for fuel gauge sender on inside of fuel level sensor 2.
25. Reach into fuel tank and release retainer tabs -arrows- below suction jet pump -2-.
26. Pull fuel level sensor 2 -1- off suction jet pump. NOTE: The sensor is shown without the fuel tank for a clearer illustration.
27. Reach into fuel tank opening on left side of vehicle and pull out suction jet pump with hoses and connecting piece toward the left. NOTE: The suction jet pump and connecting piece can be removed after removal.

Installation is carried out in the reverse order, when doing this note the following

Note. Secure all hose connections with the correct hose clips (same as original equipment).

Scheme 326

Scheme 327

Scheme 328

Scheme 329

Scheme 330

Scheme 331

Scheme 332

Scheme 333

Scheme 334

Scheme 335

Scheme 336

Scheme 337

1. Push suction jet pump (with hoses and connecting piece fitted) into fuel tank opening on right side of vehicle.
2. Reach into fuel tank opening on left side of vehicle and pull suction jet pump with hoses and connecting piece into their final position.
3. Install rigid pipe -3- into corresponding holes in accumulator -6-.
4. Press return hoses -1 and 2- onto connecting piece -4- so that the hose connectors engage. NOTE: Always install new seals -7- for return line. Ensure that the seals are not crushed; use a suitable lubricant if necessary.
5. Clip rigid pipe -3- into connecting piece -4-; at same time engage connecting piece in baffle housing -6-.
6. Insert sender for fuel gauge into guide on outer section of accumulator and press down until it clicks into place.
7. Insert hose -5- into corresponding hole in accumulator -6-.
8. Install inner section of accumulator into outer section of accumulator (in tank) so that notch -1- on inner section of housing is aligned with marking -2- on outer section of housing. It should be possible to press down the inner section of the accumulator noticeably.
9. Apply fuel pump spanner 3307 trough opening and place on accumulator.
10. Turn pump together with inner section of baffle housing clockwise (approx. 15 degrees). Notch -1- will then be aligned with marking -3- (bayonet fitting).
11. Disconnect harness connectors for fuel gauge sender on inside of flange.
12. Insert new seal for closing flange into opening of fuel tank (seal should be dry).
13. When inserting closing flange ensure that wiring -2- to fuel pump and fuel return line -1- is positioned correctly.
14. When installing, turn flange in direction of -arrow-, as in illustration.
15. Install flange in fuel tank; note correct installation position: Marking on flange -1- should be aligned with marking on fuel tank -2-. NOTE: -Arrow- points in direction of travel.
16. Tighten sealing ring (120 Nm).
17. Install supply and return hoses (according to identifying marks).
18. Install cover for flange so that the projecting part is above the electrical connector.
19. Install fuel level sensor 2 as follows: NOTE: Do not bend sender when installing.
20. Connect connectors and insert fuel level sensor 2 -1- into fuel tank.
21. Install suction jet pump -2- inside fuel tank onto fuel level sensor. Retaining tabs -arrows- must engage.
22. Install new seal for fuel level sensor 2 in fuel tank opening (seal should be dry).

Note correct position of fuel level sensor 2

1. Marking on flange -2- must be aligned with marking on fuel tank -1-.

Scheme 338

1. Tighten locking ring (120 Nm).
2. Install supply and return hoses (according to identifying marks).
3. Install cover for flange so that projecting part is above electrical connector.

See Caution for connecting Telematics battery under FUEL SUPPLY, ALL WHEEL DRIVE (AWD) .

Scheme 339

1. After connecting battery, enter anti-theft code for radio See Radio operating instructions. NOTE: With Battery re-connected, remember to activate electrical equipment (radio, clock, window switches) according to operating instructions.
2. Generate readiness code. See appropriate ON-BOARD DIAGNOSTIC (OBD) article in ENGINE PERFORMANCE.

TIGHTENING TORQUES: FUEL PUMP DELIVERY MODULE CLOSING RING (AWD)

Fuel filter - component overview

Note. Fuel filter is located in front right outside at fuel tank.

Note. The following list refers to items in (Scheme 345).

1. 2 Nm
2. Connection flange hose for fuel supply line
3. Bolt - 23 Nm (17 ft lb)
4. Sealing washer Always replace
5. Bracket For fuel filter
6. Fuel supply line From fuel tank
7. Connection flange hose for fuel supply line
8. Bolt - 23 Nm (17 ft lb)
9. Sealing washer Always replace
10. Fuel filter Under vehicle, in front of right rear wheel Flow direction is marked by an arrow Do not interchange connections
11. Fuel supply line To fuel supply line at fuel rail

Scheme 340

Fuel filter -component overview, vehicles with 8-Cylinder-Turbo engine

Note. The fuel filter is located on the right front side of the fuel tank

Note. The following list refers to items in (Scheme 346).

1. Hose clamp for Fuel filter Tighten to 0.8 Nm
2. Fuel filter Direction of flow is indicated by -arrows- Hose clamp -1-, fastens to fuel tank Connections are not interchangeable
3. Fuel hose from fuel pump
4. Hose clip Corresponding See Parts catalog .
5. Hose clip Corresponding See Parts catalog
6. Fuel hose to the fuel distribution pipe

Scheme 341

1. Container

Scheme 342

1. Remove screw -3- and pull fuel pump downward; fuel hoses -2- and -4- as well as the connector -1 remain connected.
2. Use a fuel resistant container to catch ay excess fuel. WARNING: Fuel supply lines are under pressure! Before loosening any lines, cover the connection with a rag. Release the pressure by slowly separating the connection.
3. Remove fuel hoses -1- and -2- from the fuel filter. (Scheme 348)
4. Loosen the hose clamp -arrow-.
5. Remove fuel filter

Installation is the reverse of removal

Note. Secure all hose connectors with hose clamps, which correspond to the series conditions

1. Consider the installation position of the fuel filter. -Arrow- on the filter housing points to direction of fuel flow.

TIGHTENING TORQUES: FUEL FILTER

EVAP canister/tank leak diagnostic system, servicing - FWD & AWD

Note. The following list refers to items in (Scheme 349).

1. Nut - 10 Nm (7 ft lb)
2. Cover For EVAP canister
3. Stud bolt - 15 Nm (11 ft lb)
4. Sealing part
5. Vent line To Evaporative Emission EVAP Canister Purge Regulator Valve -N80
6. Vent line From Gravity valve at fuel tank
7. Vacuum line To diagnostic Leak Detection Pump (LDP) - V144
8. Cable tie To fasten vacuum line at bracket of LDP pump
9. Leak Detection Pump (LDP) -V144- Installation position: In left rear wheelhousing below wheelhousing liner Checking, see «LEAK DETECTION PUMP (LDP) -V144-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) Removing and installing, see «LEAK DETECTION PUMP (LDP) -V144-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines)
10. 3-pin electrical harness connector Black
11. Connecting hose Diagnostic pump/EVAP canister Pressure side Press release button on diagnostic pump to disconnect
12. 10 Nm (7 ft lb)
13. Air filter For Leak Detection Pump (LDP) -V144- No service requirements
14. Sealing part
15. Cable tie To fasten connecting hose in wheelhousing
16. EVAP canister Installation position: In lower spare wheel molding Removing and installing, see «EMISSION EVAPORATIVE (EVAP) CANISTER, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__emission-evaporative-evap-canister-removing-and)

Scheme 343

Emission Evaporative (EVAP) canister, removing and installing

Note. Secure all hose connectors with hose clamps, which correspond to the series conditions

See Parts catalog

1. Check seal integrity. See «TANK LEAK DIAGNOSTIC, PERFORMING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__tank-leak-diagnostic-performing) .

Scheme 344

1. Remove cover for EVAP canister at bottom of spare tire well.
2. Loosen hose connections 1 to 3 on vent lines.
3. Remove sealing parts above vent lines.
4. Unbolt studs -arrows- and remove EVAP canister.

Installation is performed in the reverse order of the removal procedure, during installation note the following

Note. Secure all hose connectors with hose clamps, which correspond to the series conditions

See Parts catalog

TIGHTENING TORQUES: EVAP CANISTER

EVAP canister/tank leak diagnostic system, diagram - 6-cylinder naturally aspirated engine

Note. The following list refers to items in (Scheme 351).

1. Throttle Valve Control Module -J338
2. Emission Evaporative (EVAP) Canister Purge Regulator Valve -N80- Component location: Right front in engine compartment Checking: See appropriate MULTIPORT FUEL INJECTION (MFI) article.
3. Vent line From EVAP canister purge regulator valve -N80- Installation position: Right side under vehicle floor Front Wheel Drive (FWD) vehicle: Fastened to vehicle floor in area of fuel tank All Wheel Drive (AWD) vehicle: Fastened to fuel tank in fuel tank area
4. Vent line To Gravity valve at fuel tank
5. EVAP canister Component location: In lower spare wheel molding
6. Connecting hose Diagnostic pump/EVAP canister Pressure side
7. Air filter For Leak Detection Pump (LDP) -V144
8. Leak Detection Pump (LDP) -V144- Component location: In left rear wheelhousing below wheelhousing liner
9. Vacuum line To Leak Detection Pump (LDP) -V144
10. T-piece Component location: Between engine and bulkhead

Scheme 345

EVAP canister/tank leak diagnostic system, diagram - 6-cylinder turbo engine

Note. The following list refers to items in (Scheme 352).

1. To intake hoses before both turbo chargers
2. Check valve Installation position (bright/dark side): As shown, arrow shows in direction of flow.
3. Emission Evaporative (EVAP) Canister Purge Regulator Valve -N80- Component location: Right front in engine compartment Checking: See appropriate MULTIPORT FUEL INJECTION (MFI) article.
4. Vent line From EVAP canister purge regulator valve -N80- Installation position: Right side under vehicle floor Fastened at fuel tank in fuel tank area
5. Vent line To Gravity valve at fuel tank
6. EVAP canister Component location: In lower in spare wheel molding
7. Connecting hose Diagnostic pump/EVAP canister Pressure side
8. Air filter For Leak Detection Pump (LDP) -V144
9. Leak Detection Pump (LDP) -V144- Component location: In wheelhousing left rear below wheelhousing molding
10. Vacuum line To Leak Detection Pump (LDP) -V144
11. Vacuum reservoir For Leak Detection Pump (LDP) -V144
12. Check valve Installation position (bright/dark side): As shown, arrow shows in direction of flow
13. To rear upper intake hose
14. To front intake hose
15. Check valve Installation position (bright/dark side): As shown, arrow shows in direction of flow

Scheme 346

EVAP canister/tank leak diagnostic system, diagram - 8-cylinder naturally aspirated engine

1. Throttle Valve Control Module -J338
2. Emission Evaporative (EVAP) Canister Purge Regulator Valve -N80- Component location: Right front in engine compartment Checking: See appropriate MULTIPORT FUEL INJECTION (MFI) article.
3. Vent line From EVAP canister to EVAP canister purge regulator valve -N80- Installation position: Right side under vehicle floor Fastened to fuel tank in fuel tank area
4. Vent line To gravity valve on fuel tank
5. EVAP canister Component location: In lower spare wheel molding
6. Connection hose Leak Detection Pump (LDP)/EVAP canister Pressure side
7. Air filter For Leak Detection Pump (LDP) -V144
8. Leak Detection Pump (LDP) -V144- Component location: In left rear wheel housing below wheel hosing liner
9. Vacuum line To Leak Detection Pump (LDP) -V144

Scheme 347

EVAP canister/tank leak diagnostic system, diagram - 8-cylinder Turbo engine

1. Front suction tube
2. Check valves Installation position (bright/dark side): As shown in fig., the arrow points to passage direction
3. Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80- Location: Right front of engine compartment
4. to Supercharger (Right)
5. Breather pipe from Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80- Location: on the underside of vehicle fastened to fuel tank
6. Breather pipe to Gravity valve at fuel tank
7. EVAP canister Location: in the spare wheel well
8. Connection hose Diagnostic pump/EVAP canister Print page
9. Air cleaner for Leak detection pump (LDP) -V144
10. Leak detection pump (LDP) -V144 Location: Under left rear whell housing liner
11. Vacuum tube to Leak detection pump (LDP) -V144
12. to Supercharger (Left)
13. Negative pressure storage container for Leak detection pump (LDP) -V144 Location: Under left front wheel housing liner
14. to left pressure tube
15. Check valve Installation position (bright/dark side): As shown in fig., -arrow-points to passage direction
16. to single solenoid valves
17. Throttle Valve Control Module -J338

Scheme 348

The leak detection system can recognize leaks in the entire fuel system, including the main fuel tank, the EVAP canister and EVAP canister purge regulator valve -N80-.

On the mechanical side, the Leak Detection system consists of a vacuum-operated diaphragm pump (LDP pump) with a reed contact on the pump diaphragm rod. The pump receives vacuum from the intake manifold.

1. Leak Detection system is triggered; the diaphragm pump pressurizes the fuel system between 20 and 30 mbar.
2. Specified pressure is reached, the pump diaphragm remains extended and the reed contact remains in the "Open" position.
3. Pressure drops (i.e. there is a leak) the diaphragm moves back and the reed contact closes.
4. During diagnosis, first is a measurement of whether the reed contact closed within 10 seconds. If this does not occur, the tank system is then sealed.
5. However, the reed contact closes within 10 seconds, there is a leak. In this case, the pump continues to cycle for four more strokes. The Engine Control Module (ECM) measures the time for each of these four strokes until the next time the reed contact closes. The Engine Control Module (ECM) recognizes if the leak is larger than 1mm diameter and the ECM can differentiate between "Small" and "Large" leaks.
6. Leak detection is automatically triggered, shortly after each engine start. If there is an incorrect measurement, a malfunction is stored in the DTC memory. A warning will appear on the instrument panel if the malfunction has occurred during two successive drives. Also, the leak detection can also be activated using the Vehicle Diagnostic, Testing and Information System VAS 0.5051. See «TANK LEAK DIAGNOSTIC, PERFORMING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__tank-leak-diagnostic-performing) .

Automatic Evaporative Emission (EVAP) system, diagnostic leak test

If a straight automatic tank leakage diagnosis is completed, refer to diagnosis -, measuring and information system VAS 5051 in the measured value block 071. See TANK LEAK DIAGNOSTIC, PERFORMING .

Diagnostic leak test, performing

1. Observe safety precautions. See «SAFETY PRECAUTIONS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__safety-precautions) .
2. Observe rules of cleanliness. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) . NOTE: Secure all hose connectors with hose clamps, which correspond to the series conditions: See Parts catalog. Replace sealing rings and seals with assembly

1. VAS 5051

Scheme 349

1. Parking brake applied
2. Vehicles with automatic transmission: Gear selector lever in P or N
3. Vehicles with manual transmission: Gear lever in neutral
4. No DTCs in DTC memory
5. Electrical consumers switched off (radiator fan must NOT run during test)
6. Vehicle diagnosis -, measuring and information system VAS 5051 attached, vehicle self-diagnosis and vehicle system "01 - engine electronics" selected.
7. A/C switched off
8. Intake Air Temperature (IAT) less than 90°C, display group 004, display field 4.
9. Coolant Temperature less than 95°C, see display group 004, display field 3.
10. Throttle valve angle less than 10°C, see display group 003, display field 3.

Test procedure

VAS 5051

1. Touch selection -1- "04 - basic adjustment".

Scheme 350

VAS 5051

1 - Enter display group

1. Type in display group -2- "071" for "display group number 071" and confirm by touching the Q-key.

Scheme 351

VAS 5051

Scheme 352

1. Check the display in display field -1-. Desired value: "Reed closed" NOTE: If "Reed closed" is displayed, continue test. If display indicates "Reed open," briefly open and close fuel filler cap to release pressure from fuel tank. This will close the reed contact.
2. Activate basic adjustment by touching the A key.
3. Check the display in display field -4-. Desired value: "Test ON"

The system test may require a minute to complete

1. Check the display in display field -4-. Desired value: "System OK"

System is sealed; test is terminated.

1. Quit function "04 - basic adjustment" by touching the A key.

Error display

During the system test if an error was recognized, the evaluation of the error takes place.

Display on VAS 5051 in display field -4

Scheme 353

1. In the event of an error: Syst.n.i.O.

1. Check the results of the diagnosis in display field -2-. "Small leak" or "large leak"
2. Quit function "04 - basic adjustment" by touching A key.

The system recognized a fine or a rough leakage

1. For tank system and tank ventilation system on leakage test, see «CHECKING FUEL SUPPLY AND TANK VENTILATION SYSTEM FOR LEAKS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__checking-fuel-supply-and-tank-ventilation) .
2. Repeat the leakage diagnosis test again.

Description

The leak detection threshold has recently changed from 1.0 mm (0.040 in.) to 0.5 mm (0.020 in.). These changes to EPA regulations regarding EVAP system integrity indicated that additional resources for more accurate EVAP system diagnosis are necessary.

The KLI9210 EVAP Tester allows testing using nitrogen to pressurize the EVAP system and a smoke generator or ultrasonic tester to locate the source of EVAP system concerns.

The following procedure will outline general use of the KLI9210 EVAP Tester. It is intended as a guideline, as EVAP systems vary between models.

Test EVAP system using Leak Detection Pump (LDP) -V144- (m.y. 1998 and later)

For vehicles without LDP, proceed to "Perform EVAP tester self-test".

For vehicles with LDP

1. Perform leak test using VAS 5051 Scan Tool and Basic Setting mode. See «LEAK DETECTION PUMP (LDP) -V144-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

If vehicle fails above test ("System not OK")

1. Verify fuel cap is properly closed; repeat test.

If "System OK" after re-test

1. Erase DTC memory (if necessary).
2. Repeat test several times to ensure proper EVAP system operation (remove and re-install fuel cap before each test).
3. Perform quality check and return vehicle to customer.

Note. If the vehicle passes the above EVAP system test, DTCs may be sporadic; the entire EVAP system should be carefully inspected.

If VAS 5051 continues to indicate "System not OK" after re-test, proceed to next step.

Perform EVAP tester self-test

Note. Always perform system self-test of KLI9210 EVAP Tester prior to use to ensure that there are no leaks. Refer to KLI9210 instruction manual for specific instructions.

1. Connect vehicle interface hose to self-test port -1-, ensuring that fitting is finger-tight. Over-tightening will damage fitting.
2. Turn control valve -2- to "Test". Gauge -3- should read 14 + 1 in. of water.

If gauge does not read 14 + 1 in. of water

Scheme 354

Scheme 355

1. Verify that valve on EVAP tester nitrogen cylinder is open and that cylinder has sufficient pressure before continuing.
2. Turn fine adjust regulator knob (arrow) until gauge reads 14 in. of water; tighten lock nut. NOTE: If gauge still does not read within above range, contact K-Line Customer Service - Technical Support for additional instructions before continuing.
3. Check flow meter -4-. (upper illustration). Meter must indicate no flow.
4. Turn control valve to "Hold" position.
5. Check gauge. Gauge must hold pressure

If gauge leaks down

1. Verify that vehicle interface hose is firmly seated and repeat previous six steps before continuing.

If gauge continues to leak down

1. Use ultrasonic tester (described later) to locate and repair leak before continuing.

Note. If the leak cannot be located or repaired, contact K-Line Customer Service - Technical Support.

Calibrate KLI9210 Tester

Determine vehicle leak threshold

To m.y. 2000: leak threshold 0.040 in.

From m.y. 2001: leak threshold 0.020 in.

Scheme 356

1. Attach test hose to appropriate preset port (black arrows).
2. Turn control valve from "Hold" to "Test".
3. Set flow meter flag (white arrow) at indicated value on flow meter.
4. Turn control valve to "Hold"; remove test hose.

Scheme 357

1. Connect fuel cap tester to hose.
2. Screw fuel cap tightly to cap receiver (arrow).
3. Turn control valve to "Test".
4. Read flow meter on tester.

If no flow is indicated

1. Proceed to "Test LDP for internal leaks".

If flow is indicated

1. Replace fuel cap and re-test.

If new fuel cap shows no flow

1. Repeat Leak Test, with new fuel cap installed, using VAS 5051 and Basic Settings mode. See «LEAK DETECTION PUMP (LDP) -V144-, CHECKING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

If Leak Test shows "System OK"

1. Perform quality check and return vehicle to customer.

Test LDP -V144- for internal leaks

If vehicle is not LDP-equipped, proceed to "Test EVAP system".

1. Clamp off LDP outlet (EVAP side) using Special Tool No. 3094 or equivalent. CAUTION: Clamp only soft rubber lines when isolating a leak. To avoid risk of damage, never clamp hard plastic lines!
2. Repeat Leak Test using VAS 5051 and Basic Setting mode. VAS 5051 should immediately indicate "System OK"
3. Repeat test several times to verify result. If test continues to indicate "System OK", remove clamp and proceed to "Test EVAP System".

If VAS 5051 indicates "System not OK"

1. Replace LDP and repeat test. If VAS 5051 indicates "System OK" after LDP is replaced and test result is verified
2. Perform quality check and return vehicle to customer.

Test EVAP System

Also see FUEL TANK, LEAK DIAGNOSTIC SYSTEM .

If vehicle is not LDP-equipped

1. Plug or clamp EVAP canister outlet and proceed to step "Continued for all vehicles" (below).

If vehicle is LDP-equipped

Scheme 358

Scheme 359

1. Plug or clamp LDP inlet (filter side) using Special Tool No. 3094 or equivalent.
2. Attach fuel cap adapter to filler neck (arrow) and test hose to adapter.
3. Turn control valve from "Hold" to "Test".
4. Allow fuel system to pressurize. NOTE: Fuel system pressurization depends on volume of fuel system and amount of fuel in tank. If fuel system pressurization does not stabilize
5. Verify all fuel system outlets have been sealed before continuing. CAUTION: Clamp only soft rubber lines when isolating a leak. To avoid risk of damage, never clamp hard plastic lines! NOTE: Any flow shown on flow meter indicates a leak. Flow before flow meter flag set at vehicle leak standard may indicate a sporadic DTC. If flow meter on tester registers flow near or above preset pressure
6. Clamp off hose (arrow) leading from EVAP purge regulator valve -N80- to intake manifold (pictured: AHA engine in A6).

If flow stops

1. Replace EVAP purge regulator valve -N80- and repeat test before continuing.

If meter indicates no flow after test

1. Perform a quality check and return vehicle to customer.

If flow continues, proceed as follows

Method 1: Locate leak with smoke generator

1. Connect leads from smoke generator to vehicle battery.
2. Use smoke generator trigger to charge fuel system with smoke.
3. Inspect complete EVAP system for escaping smoke.

Method 2: Locate leak with ultrasonic tester

General search: tester only

Localized search: tester with extension (on left in illustration)

Scheme 360

If leak cannot be located

1. Disconnect and plug or clamp shut EVAP lines to isolate fuel tank, using Special Tool No. 3094 or equivalent, before continuing.

If flow stops

1. Reconnect EVAP lines to search area that was isolated.

If leak or source of fuel odor cannot be found

1. Contact Audi Dealer Technician Helpline.

When leak has been located

1. Repair leak and repeat EVAP system test.
2. Perform quality check and return vehicle to customer. NOTE: Because leak may be at top of fuel tank, it may not be possible to locate through fuel pump/sending unit access plate. Fuel tank may need to be lowered to locate the leak.

Tank leak diagnostic, performing

1. Observe safety precautions. See «FUEL SUPPLY SYSTEM COMPONENTS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .
2. Observe safety precautions. See «RULES OF CLEANLINESS»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__rules-of-cleanliness) .

Special tools and test equipment

1. VAS 5051 with VAS 5051/1

Scheme 361

Note. Fasten all hose connection with hose clamps used in production: Parts catalog Always replace seals, O-rings and gaskets.

Checking fuel supply and tank ventilation system for leaks

Note. The following describes areas in the fuel supply and ventilation system that should be checked for possible leaks. After making necessary repairs, perform leak test again to ensure that all leaks were successfully repaired.

1. Switch ignition off.
2. Check if fuel filler cap was completely closed for test.
3. Check if seal of fuel filler cap is damaged, replace if necessary.

Limosine

1. Remove cover for sender for fuel gauge located under liner in luggage compartment.

Avant

1. Remove cover for sender for fuel gauge located under liner in luggage compartment.

See CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING or CARGO AREA FLOOR TRIM AND SUPPORTS (VEHICLES WITH CHILDREN'S BENCH), REMOVING AND INSTALLING .

All

1. Rear closing flange: Remove liner for luggage. Unbolt closing flange.

Scheme 362

Vehicles with all wheel drive

Scheme 363

1. Remove rear seat See «REAR SEATS»(/audi/a6/c5-1997-2001/remont/seats/#seats-frames) .
2. Remove the screws -arrows- for the catch flange cover

Note. Observe installation notes for closing flanges. See INSTALLING (FWD vehicles), or INSTALLING (AWD), or INSTALLING (Fuel Supply Sensor 3 -G237-).

All

1. Check whether seals under connection flanges are OK and ring nuts are properly tightened. Also check if fuel line connections are tight.
2. Visually check all lines and hose connections of tank ventilation system and replace leaky lines. For example: Line EVAP canister to Evaporative Emission (EVAP) Canister Purge Regulator Valve (in engine compartment). Lines from EVAP canister to Leak Detection Pump (LDP) (under left rear wheelhousing liner). Line from fuel tank to EVAP canister (beneath cover for EVAP canister) Lines from EVAP system (tank ventilation system) below right rear wheelhousing liner. Fuel lines to engine. NOTE: Leaks at lines and components of fuel supply system can sometime be located using a non-flammable, environmentally sound leak detection spray. For this, initiate leak test several times in sequence to build pressure in the system. Leaks can be detected via bubbles forming at the leak.
3. Visually check components of fuel supply system and EVAP system. Fuel tank EVAP canister Leak Detection Pump (LDP) -V144- Evaporative Emission (EVAP) canister purge regulator valve -N80

Note. Because of the shape or function of these components it is not always possible to detect leaks by applying spray. It may be necessary to clamp off the relevant component using 3094 hose clamp and initiate the leak detection diagnostic. If the leak is no longer detected, the component that was clamped off is faulty. If the clamp is directly on the diagnostic pump and a leak is still detected, then the diagnostic pump itself is leaking.

1. Checking Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80

See appropriate MULTIPORT FUEL INJECTION (MFI) article.

Scheme 364

Scheme 365

1. VAG1526 A
2. VAG1527 B
3. VAG1594 A
4. VAG1598/22 (Vehicles with mechanical accelerator linkage)
5. VAG1598/31 (Vehicles with Electronic throttle [drive by wire)
6. VAS5051 with VAS5051/1 or
7. VAG1551 with VAG1551/3 A

1. Ignition switched on
2. Vehicle diagnosis - measuring and information system VAS 5051 attached, vehicle self-diagnosis and vehicle system "01 - engine electronics" selected.

VAS 5051 selection screen

Scheme 366

1. Select the diagnostic function -1- "03 - control module diagnosis".
2. Touch key until the leakage diagnostic pump/tank ventilation system is started.

1. The diagnostic pump for fuel system is running for approximately 1 minute.

Note. The noise of the diagnostic pump (running) is audible at the rear left wheel housing.

1. Quit function "03 - control module diagnosis" by touching <= key
2. Select "06 - End output"
3. Switch ignition off

If diagnostic pump is not activated (no operating noise audible)

1. Remove Leak Detection Pump (LDP) -V144- and disconnect connector.

Internal resistance test

1. Connect circuit analyzer as follows to perform resistance test.

LEAK DETECTION PUMP: RESISTANCE TEST

Scheme 367

Desired values are not reached

1. Replace Leak Detection Pump (LDP) -V144-. See «LEAK DETECTION PUMP (LDP) -V144-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Desired values are reached

1. Test voltage supply for Leak Detection Pump (LDP) -V144-. See «VOLTAGE SUPPLY TEST»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__voltage-supply-test) .

Voltage supply test

Note. Voltage supply for the diagnostic pump is made by the fuel pump relay.

Test condition

1. Safety device for diagnostic pump i.O..

1. Connect V.A.G 1527 B as follows

LEAK DECTION PUMP VOLTAGE SUPPLY CIRCUIT TEST: TERMINAL 3

Scheme 368

1. Briefly operate the starter Light Emitting Diode (LED) must flash

If light emitting diode does not shine

Scheme 369

1. Check the electrical harness for an open from terminal 3 over the fuse to the fuel pump relay according to the electrical schematics.
2. If necessary, repair wiring problem using circuit diagram.

Output circuit checking - Vehicles with mechanical accelerator operation

1. Connect VAG 1527 B as follows: LEAK DECTION PUMP VOLTAGE SUPPLY CIRCUIT TEST: TERMINAL 2 Connector Terminal Measure aginst 2 Battery Pos. (+)
2. Begin output check diagnosis and activate the diagnosis pump. See «TEST PROCEDURE»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Light Emitting Diode (LED) must flash

If Light Emitting Diode (LED) does not flash

Scheme 370

1. Quit function "03 - control module diagnosis" by touching left arrow key.
2. Select "06 - End output"
3. Switch ignition off.
4. Connect test box VAG1598/31 to the circuit harness connector; do not connect the ECM. See appropriate MULTIPORT FUEL INJECTION (MFI) article. WARNING: To avoid damaging electrical components, select the appropriate measurement settings on the measuring device before connecting to the components.
5. Check the following circuit connections for open circuits and shorts to ground and/or battery positive (+): LEAK DECTION PUMP OUTPUT CIRCUIT TEST: TERMINAL 2 Connector terminal Test box V.A.G 1598/22 Socket 2 16
6. Repair short circuit and/or circuit malfunction using circuit diagram.

If no problem is found, but the diagnosis pump still does not work during the Output check diagnosis

1. Replace Leak Detection Pump (LDP). See «LEAK DETECTION PUMP (LDP) -V144-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Input circuit checking - Vehicles with mechanical accelerator operation

1. Input circuit checking - Vehicles with mechanical accelerator operation.

See appropriate MULTIPORT FUEL INJECTION (MFI) article.

Scheme 371

1. Check the following circuit connections for open circuits and shorts to ground and/or battery positive (+): LEAK DETECTION PUMP INPUT CIRCUIT TEST: TERMINAL 37 (VEHICLES WITH MECHANICAL ACCELERATOR OPERATION) Connector terminal Test box V.A.G 1598/22 Socket 1 37
2. Repair short circuit and/or circuit malfunction using circuit diagram

Scheme 372

1. Connect VAG 1527 B as follows: LEAK DETECTION PUMP OUTPUT CIRCUIT TEST: TERMINAL 2 (VEHICLES WITH ELECTRONIC ENGINE POWER CONTROL, DRIVE-BY WIRE) Connector terminal Measure aginst 2 Battery Pos. (+)
2. Begin output check diagnosis and activate the diagnosis pump. See «TEST PROCEDURE»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) . Light Emitting Diode (LED) must flash

If Light Emitting Diode (LED) does not flash

1. Quit function "03 - control module diagnosis" by touching left arrow
2. Select "06 - End output"
3. Switch ignition off
4. Connect test box VAG1598/31 to the circuit harness connector; do not connect the ECM. Connect the ground clip of the test box to ground (not shown in illustration).

See appropropriate MULTIPORT FUEL INJECTION (MFI) article.

Scheme 373

Scheme 374

1. Check the following circuit connections for open circuits and shorts to ground and/or battery positive: LEAK DETECTION PUMP OPEN/SHORT CIRCUIT TEST: TERMINAL 2 (VEHICLES WITH ELECTRONIC ENGINE POWER CONTROL, DRIVE-BY WIRE) Connector terminal Test box VAG 1598/31 Socket 2 25
2. Repair circuit malfunction using circuit diagram

If no problem is found, but the diagnosis pump still does not work during the Output check diagnosis

1. Replace Leak detection pump (LDP) -V144-. See «LEAK DETECTION PUMP (LDP) -V144-, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Scheme 375

Scheme 376

1. Connect test box VAG1598/31 to the circuit harness connector; do not connect the ECM. Connect the ground clip of the test box to ground (not shown in illustration). See appropropriate MULTIPORT FUEL INJECTION (MFI) article. WARNING: To avoid damaging electrical components, select the appropriate measurement settings on the measuring device before connecting to the components.
2. Check the following circuit connections for open circuits and shorts to ground and/or battery positive: LEAK DETECTION PUMP INPUT CIRCUIT TEST: TERMINAL 1 (VEHICLES WITH ELECTRONIC ENGINE POWER CONTROL, DRIVE-BY WIRE) Connector terminal Test box VAG 1598/31 Socket 1 80
3. Repair circuit malfunction using circuit diagram

Scheme 377

1. Unbolt left rear wheel.
2. Remove left rear wheelhousing liner. See «WHEELHOUSING LINER, REAR»(/audi/a6/c5-1997-2001/remont/mirrors/#exterior-equipment__wheelhousing-liner-rear) .
3. Cut cable tie -1- and disconnect hose -2-.
4. After releasing locking tab pull hose coupling -3- off.
5. Unscrew nuts -arrows-.
6. Remove LDP and with ignition switched off disconnect harness connector -2-.

Installation is the reverse of removal, note the following

1. Secure hose -2- with cable tie to bracket of LDP.

Scheme 378

Bracket for leak detection pump at wheel housing: 7.5 Nm.

TIGHTENING TORQUES: LEAK DETECTION PUMP

Accelerator pedal cable, removing and installing

Note. When installing the accelerator pedal cable, make sure that it is properly aligned between the supports and attachment points.

Scheme 379

Scheme 380

Scheme 381

Scheme 382

Scheme 383

1. Remove driver's side storage shelf. See «DRIVER'S STORAGE COMPARTMENT, REMOVING»(/audi/a6/c5-1997-2001/remont/mirrors/#interior-equipment__drivers-storage-compartment-removing) .
2. Disconnect accelerator pedal cable end -1- at top of accelerator pedal -2-.
3. Pull rubber gasket off toward front -arrows-.
4. Remove plenum chamber cover -1- toward front.
5. Remove engine cover -arrows-.
6. Disconnect vacuum line -1- at vacuum unit for cruise control.
7. Remove bolts -arrows- for bracket of vacuum unit -2- for cruise control.
8. Disconnect actuation rod at throttle valve control module.
9. Remove clip -3- for accelerator pedal cable sleeve.
10. Disconnect nipple -1- at accelerator pedal cable end from cable disk.
11. Remove accelerator pedal cable together with rubber bearing -4- from support -2-.

Vehicles with automatic transmission

1. Disconnect harness connector -2- at kickdown switch.

Scheme 384

1. Remove clip -1- at accelerator pedal cable support or kickdown switch.

Note. For vehicles equipped with a manual transmission, the clip is located behind the bulkhead.

Scheme 385

1. Turn accelerator pedal cable attachment approx. 1/4 -turn (90°) counter clockwise -arrow- -1- and pull from bulkhead -arrow- -2-.
2. Remove accelerator pedal cable.

1. Observe notes and cautions under «ACCELERATOR PEDAL (AP) CABLE, SERVICING - VEHICLES WITH MECHANICAL ACCELERATOR MECHANISM»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines) .

Vehicles with manual transmission

1. Push accelerator pedal cable together with support -3- and accelerator pedal cable attachment -1- from engine compartment through both bulkheads in direction of arrow.
2. Secure accelerator pedal cable support with clamp -2- from behind bulkhead in plenum chamber.

Scheme 386

Scheme 387

1. Push accelerator pedal cable together with support -3- and attachment -1- from plenum chamber to outside through bulkhead and to rear through bulkhead toward interior of car. -Arrow- shows direction of installation.
2. Secure accelerator pedal cable support with clip -1- from in front of bulkhead.
3. Reconnect harness connector for kickdown switch -2-.

Scheme 388

Scheme 389

1. Install accelerator attachment after inserting it into bulkhead by turning it clockwise in direction of arrow -1- approx. 1/4 -turn (90°) -arrow-2-.

The remainder of the installation is the reverse of removal, however note the following

1. Adjust accelerator pedal cable. See «ACCELERATOR PEDAL CABLE, ADJUSTING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__accelerator-pedal-cable-adjusting) .

Accelerator pedal cable, adjusting

1. Accelerator pedal cable -1- must be attached to accelerator pedal and at lever of throttle valve control module. see scheme 399

1. Remove clip -3- for accelerator pedal cable.
2. Depress accelerator pedal fully.

Scheme 390

Note. For this step, a second technician or a brace (between the steering wheel and the pedal) is required to press the pedal down.

1. To adjust accelerator pedal cable, secure it with clip -3- at support -2- in such a way that throttle valve lever is at Wide Open Throttle (WOT).

1. To adjust accelerator pedal cable, secure it with clip at support -2- in such a way that throttle valve lever is at Wide Open Throttle (WOT) and kickdown switch clicks audibly.

All vehicles

1. Release accelerator pedal or remove brace.
2. After adjusting engine idle, check Closed Throttle Position (CTP), and Wide Open Throttle (WOT) stops.

Scheme 391

Scheme 392

1. VAG 1526 A
2. VAG 1594 A

Scheme 393

1. Remove storage compartment on drivers side: See «DRIVER'S STORAGE COMPARTMENT, REMOVING»(/audi/a6/c5-1997-2001/remont/mirrors/#interior-equipment__drivers-storage-compartment-removing) .
2. Disconnect 2-pin harness connector off Kick-Down switch - F8 -in front engine compartment (at bulkhead).
3. Connect multimeter to Kick-Down switch (resistance test range). Specification: infinitive Ohm (no continuity)
4. Slowly press Kick-Down switch. Shortly after kick-down point the reading must drop to 0 Ohm. Accelerator pedal should be just before stop.

If specification are not obtained

1. Adjust Accelerator Pedal (AP) cable. See «ACCELERATOR PEDAL CABLE, ADJUSTING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines__accelerator-pedal-cable-adjusting) .

Accelerator Pedal (AP), servicing - vehicles with Electronic Power Control (EPC) (drive by wire)

Note. The following list refers to items in see scheme 403.

1. Accelerator pedal module With Throttle Position (TP) Sensor -G79 and Sender -2- for accelerator pedal position -G185- Removing and installing, see «ACCELERATOR PEDAL (AP) WITH POSITION SENSORS, REMOVING AND INSTALLING»(/audi/a6/c5-1997-2001/remont/fuel-system/#fuel-supply-system-all-engines)
2. 10 Nm (7 ft lb)
3. 6 pin connector
4. 10 Nm (7 ft lb)

Scheme 394

1. Remove storage compartment on drivers side: See «DRIVER'S STORAGE COMPARTMENT, REMOVING»(/audi/a6/c5-1997-2001/remont/mirrors/#interior-equipment__drivers-storage-compartment-removing) .
2. Disconnect 6 pin connector -2-.
3. Remove screws -1- and -3-.
4. Remove the accelerator pedal (AP) module.

Installation is the reverse of removal

1. For vehicles with automatic transmission, the kick down function must be learned

For 2.7L BiTurbo engine, see KICK-DOWN FUNCTION, ADAPTATION . For 2.8L V6 (ATQ) engine, see KICK DOWN FUNCTION, ADAPTING . For 3.0L V6 engine, see KICKDOWN FUNCTION, ADAPTATION .

Scheme 395

TIGHTENING TORQUES: ACCELERATOR PEDAL MODULE

See also:
• EMERGENCY BATTERY, SWITCHING OFF/ON
• CARGO AREA FLOOR TRIM AND SUPPORTS (AVANT), REMOVING AND INSTALLING
• WHEELHOUSING LINERS, REMOVING AND INSTALLING
• REAR SEATS
• WHEELHOUSING LINER, REAR
• EXHAUST SYSTEM - 2.8L V6 AHA, ATQ
• DRIVER'S STORAGE COMPARTMENT, REMOVING
• KICK DOWN FUNCTION, ADAPTING
• SAFETY PRECAUTIONS
• RULES OF CLEANLINESS
• FUEL TANK, DRAINING
• FUEL TANK, DRAINING
• CHECKING PROCEDURE OF GROUND (GND) CONNECTION
• B - PROCEDURE ON FUEL TANK THAT CONTAINS LESS THAN 3/4FUEL
• FUEL SUPPLY, FRONT WHEEL DRIVE (FWD)
• INSTALLATION POSITION OF GROUND WIRE
• FUEL SUPPLY, ALL WHEEL DRIVE (AWD)
• FUEL TANK WITH ATTACHMENTS, REMOVING AND INSTALLING - VEHICLES WITH 8-CYLINDER ENGINE EXCEPT A6 ALLROAD
• SENDER FOR FUEL GAUGE -G-, REMOVING AND INSTALLING
• FUEL LEVEL SENSOR 2 -G169-, REMOVING AND INSTALLING
• RELEASE HARNESS CONNECTOR
• COMPONENT OVERVIEW, TRANSFER FUEL PUMP (FP) -G23
• FUEL SUPPLY SENSOR 3 -G237-, REMOVING AND INSTALLING
• EMISSION EVAPORATIVE (EVAP) CANISTER, REMOVING AND INSTALLING
• TANK LEAK DIAGNOSTIC, PERFORMING
• CHECKING FUEL SUPPLY AND TANK VENTILATION SYSTEM FOR LEAKS
• VOLTAGE SUPPLY TEST
• ACCELERATOR PEDAL CABLE, ADJUSTING